Intermediate film for laminated glass, laminated glass and method for fitting laminated glass

ABSTRACT

There is provided an interlayer film for laminated glass which is high in heat shielding properties. The interlayer film for laminated glass according to the present invention includes an infrared ray reflection layer which reflects infrared rays, a first resin layer which is arranged on a first surface side of the infrared ray reflection layer and contains a thermoplastic resin and a second resin layer which is arranged on a second surface side of the infrared ray reflection layer and contains a thermoplastic resin, and the infrared ray transmittance in the wavelength of 780 to 2100 nm of the first resin layer is higher by 10% or more than the infrared ray transmittance in the wavelength of 780 to 2100 nm of the second resin layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of patent application Ser.No. 15/111,330 filed on Jul. 13, 2016, which is 371 application ofApplication Serial No. PCT/JP2015/052773, filed on Jan. 30, 2015, whichis based on Japanese Patent Application Nos. 2014-016453 and2014-016454, filed on Jan. 31, 2014, the entire contents of which arehereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to an interlayer film for laminated glassused for laminated glass of automobiles, buildings and the like.Moreover, the present invention relates to laminated glass prepared withthe interlayer film for laminated glass and a method for fittinglaminated glass.

BACKGROUND ART

Since laminated glass generates only a small amount of scattering glassfragments even when subjected to external impact and broken, laminatedglass is excellent in safety. As such, the laminated glass is widelyused for automobiles, railway vehicles, aircraft, ships, buildings andthe like. The laminated glass is produced by sandwiching an interlayerfilm for laminated glass between a pair of glass plates. Such laminatedglass used for the opening part of vehicles and buildings is required tohave high heat shielding properties.

The energy amount of an infrared ray with a wavelength greater than orequal to 780 nm which is longer than that of visible light is small ascompared with an ultraviolet ray. However, the thermal action ofinfrared rays is large, and when infrared rays are absorbed into asubstance, heat is released from the substance. As such, infrared raysare generally called heat rays. Thus, in order to enhance the heatshielding properties of laminated glass, it is necessary to sufficientlycut off infrared rays.

As an interlayer film including heat shielding particles for effectivelycutting off the infrared rays (heat rays), the following Patent Document1 discloses an interlayer film including tin-doped indium oxideparticles (ITO particles) or antimony-doped tin oxide particles (ATOparticles). The following Patent Document 2 discloses an interlayer filmincluding tungsten oxide particles.

RELATED ART DOCUMENT Patent Document

Patent Document 1: WO 2001/025162 A1

Patent Document 2: WO 2005/087680 A1

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In recent years, laminated glass prepared with an interlayer film isrequired to achieve both high heat shielding properties and high visiblelight transmittance (Visible Transmittance) at the same time. That is,with regard to the laminated glass, it is necessary to enhance the heatshielding properties while maintaining the visible light transmittancehigh.

However, there are cases where high heat shielding properties and highvisible light transmittance cannot be achieved at the same time by theconventional laminated glass such as those described in Patent Documents1 and 2.

An object of the present invention is to provide an interlayer film forlaminated glass which is high in heat shielding properties, laminatedglass prepared with the interlayer film for laminated glass and a methodfor fitting laminated glass.

An object of the present invention with limitation is to provide aninterlayer film for laminated glass which is high in heat shieldingproperties and is high in visible light transmittance, and an object ofthe present invention with limitation is to provide laminated glassprepared with the interlayer film for laminated glass and a method forfitting laminated glass.

Means for Solving the Problems

According to a broad aspect of the present invention, there is providedan interlayer film for laminated glass including an infrared rayreflection layer which reflects infrared rays, a first resin layer whichis arranged on a first surface side of the infrared ray reflection layerand contains a thermoplastic resin, and a second resin layer which isarranged on a second surface side opposite to the first surface of theinfrared ray reflection layer and contains a thermoplastic resin, andthe infrared ray transmittance in the wavelength of 780 to 2100 nm ofthe first resin layer being higher by 10% or more than the infrared raytransmittance in the wavelength of 780 to 2100 nm of the second resinlayer.

The infrared ray transmittance in the wavelength of 780 to 2100 nm ofthe first resin layer is preferably higher by 30% or more than theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond resin layer.

In a specific aspect of the interlayer film for laminated glassaccording to the present invention, the infrared ray reflection layer isa resin film with metal foil, a multilayer laminated film in which ametal layer and a dielectric layer are formed on a resin layer, amultilayer resin film or a liquid crystal film.

It is preferred that at least one among the first resin layer and thesecond resin layer contain an adhesive force regulating agent. It ismore preferred that both of the first resin layer and the second resinlayer contain an adhesive force regulating agent.

In another specific aspect of the interlayer film for laminated glassaccording to the present invention, the second resin layer containsmetal oxide particles.

In yet another specific aspect of the interlayer film for laminatedglass according to the present invention, the metal oxide particles aretin-doped indium oxide particles or tungsten oxide particles.

In a different specific aspect of the interlayer film for laminatedglass according to the present invention, the second resin layercontains at least one kind among a phthalocyanine compound, anaphthalocyanine compound and an anthracyanine compound.

In a different specific aspect of the interlayer film for laminatedglass according to the present invention, the thermoplastic resin in thefirst resin layer is a polyvinyl acetal resin and the thermoplasticresin in the second resin layer is a polyvinyl acetal resin.

In a further different specific aspect of the interlayer film forlaminated glass according to the present invention, the first resinlayer contains a plasticizer and the second resin layer contains aplasticizer.

In another specific aspect of the interlayer film for laminated glassaccording to the present invention, the first resin layer contains anultraviolet ray shielding agent.

In yet another specific aspect of the interlayer film for laminatedglass according to the present invention, the second resin layercontains an ultraviolet ray shielding agent.

According to a broad aspect of the present invention, there is providedlaminated glass including a first laminated glass member, a secondlaminated glass member and an interlayer film for laminated glassdescribed above, wherein the interlayer film for laminated glass isarranged between the first laminated glass member and the secondlaminated glass member, the first laminated glass member is arranged onthe outside of the first resin layer in the interlayer film forlaminated glass, and the second laminated glass member is arranged onthe outside of the second resin layer in the interlayer film forlaminated glass.

In a specific aspect of the laminated glass according to the presentinvention, the infrared ray transmittance in the wavelength of 780 to2100 nm of the first laminated glass member is higher than the infraredray transmittance in the wavelength of 780 to 2100 nm of the secondlaminated glass member.

In a specific aspect of the laminated glass according to the presentinvention, the infrared ray transmittance in the wavelength of 780 to2100 nm of the first laminated glass member is higher by 10% or morethan the infrared ray transmittance in the wavelength of 780 to 2100 nmof the second laminated glass member.

According to a broad aspect of the present invention, there is provideda method for fitting the above-described laminated glass for a buildingor a vehicle into an opening part between an outer space and an innerspace into which heat rays are made incident from the outer space,including the step of fitting the laminated glass into the opening partso that the first laminated glass member is positioned at the outerspace side and the second laminated glass member is positioned at theinner space side.

Effect of the Invention

Since the interlayer film for laminated glass according to the presentinvention allows the first resin layer, the infrared ray reflectionlayer and the second resin layer to be superposedly arranged in thisorder and the infrared ray transmittance in the wavelength of 780 to2100 nm of the first resin layer is higher by 10% or more than theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond resin layer, it is possible to enhance the heat shieldingproperties of laminated glass prepared with the interlayer film forlaminated glass.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a partially cut-away sectional view showing an interlayer filmfor laminated glass in accordance with one embodiment of the presentinvention.

FIG. 2 is a partially cut-away sectional view showing laminated glassprepared with an interlayer film for laminated glass in accordance withone embodiment of the present invention.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be elucidated by describingspecific embodiments and examples of the present invention withreference to the drawings.

FIG. 1 shows laminated glass prepared with an interlayer film forlaminated glass in accordance with one embodiment of the presentinvention schematically represented as a partially cut-away sectionalview.

An interlayer film 1 shown in FIG. 1 is a multilayer interlayer film.The interlayer film 1 is used for obtaining laminated glass. Theinterlayer film 1 is an interlayer film for laminated glass. Theinterlayer film 1 is provided with an infrared ray reflection layer 2, afirst resin layer 3 arranged on a first surface 2 a side of the infraredray reflection layer 2 and a second resin layer 4 arranged on a secondsurface 2 b side opposite to the first surface 2 a of the infrared rayreflection layer 2. The first resin layer 3 is layered on the firstsurface 2 a of the infrared ray reflection layer 2. The second resinlayer 4 is layered on the second surface 2 b of the infrared rayreflection layer 2. The infrared ray reflection layer 2 is anintermediate layer and has heat ray reflecting performance. In thepresent embodiment, the first and second resin layers 3 and 4 aresurface layers. The infrared ray reflection layer 2 is arranged betweenthe first and second resin layers 3 and 4. The infrared ray reflectionlayer 2 is sandwiched between the first and second resin layers 3 and 4.Accordingly, the interlayer film 1 has a multilayer structure in whichthe first resin layer 3, the infrared ray reflection layer 2 and thesecond resin layer 4 are layered in this order.

In this connection, other layers may be arranged between the infraredray reflection layer 2 and the first resin layer 3 and between theinfrared ray reflection layer 2 and the second resin layer 4,respectively. It is preferred that the first resin layer 3 and thesecond resin layer 4 each be directly layered on the infrared rayreflection layer 2. Examples of another layer include a layer containinga thermoplastic resin such as a polyvinyl acetal resin, a layercontaining polyethylene terephthalate, polyethylene naphthalate and thelike, and a layer formed of an inorganic compound such as metal foil. Inthe case where such other layers are included, only one kind of thelayer may be included and two or more kinds of different layers may beincluded.

The infrared ray reflection layer reflects infrared rays. The infraredray reflection layer is not particularly limited as long as the layerhas infrared ray reflecting performance. Because the infrared rayreflection layer is allowed to be excellent in infrared ray reflectingperformance, it is preferred that the infrared ray reflection layer havea characteristic having the infrared ray transmittance of less than orequal to 40% in at least one wavelength within the range of 800 to 2000nm. In this connection, the infrared ray transmittance of an infraredray reflection layer used in the example described below satisfies theabove-mentioned preferred condition. In at least one wavelength withinthe range of 800 to 2000 nm, the infrared ray transmittance is morepreferably less than or equal to 30% and further preferably less than orequal to 20%.

Examples of the infrared ray reflection layer include a resin film withmetal foil, a multilayer laminated film in which a metal layer and adielectric layer are formed on a resin layer, a film containinggraphite, a multilayer resin film, a liquid crystal film, and the like.These films have infrared ray reflecting performance.

It is especially preferred that the infrared ray reflection layer be aresin film with metal foil, a film containing graphite, a multilayerresin film or a liquid crystal film. These films are highly excellent ininfrared ray reflecting performance. Accordingly, by the use of thesefilms, it is possible to obtain laminated glass in which the heatshielding properties are further enhanced and high visible lighttransmittance can be maintained over a longer period of time. Theinfrared ray reflection layer may be a resin film with metal foil, amultilayer resin film or a liquid crystal film.

The resin film with metal foil is provided with a resin film and metalfoil layered on the outer surface of the resin film. Examples of thematerial for the resin film include a polyethylene terephthalate resin,a polyethylene naphthalate resin, a polyvinyl acetal resin, anethylene-vinyl acetate copolymer resin, an ethylene-acryl copolymerresin, a polyurethane resin, a polyvinyl alcohol resin, a polyolefinresin, a polyvinyl chloride resin, a polyimide resin and the like.Examples of the material for the metal foil include aluminum, copper,silver, gold, palladium, an alloy containing these metals, and the like.

The multilayer laminated film in which a metal layer and a dielectriclayer are formed on a resin layer is a multilayer laminated film inwhich metal layers and dielectric layers are alternately layered in anarbitrary number of layers on a resin layer (resin film).

Examples of the material for the resin layer (resin film) in themultilayer laminated film include the same material as the material forthe resin film in the resin film with metal foil. Examples of thematerial for the resin layer (resin film) in the multilayer laminatedfilm include polyethylene, polypropylene, polylactic acid,poly(4-methylpentene-1), polyvinylidene fluoride, a cyclic polyolefin,polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol, apolyamide such as nylon 6, 11, 12 and 66, polystyrene, polycarbonate,polyethylene terephthalate, polyethylene naphthalate, polyester,polyphenylene sulfide, polyetherimide and the like. Examples of thematerial for the metal layer in the multilayer laminated film includethe same material as the material for the metal foil in the resin filmwith metal foil. On both sides or on one side of the metal layer, a coatlayer of a metal or a mixed oxide can be provided. Examples of thematerial for the coat layer include ZnO, Al₂O₃, Ga₂O₃, InO₃, MgO, Ti,NiCr, Cu and the like.

Examples of the material for the dielectric layer in the multilayerlaminated film include indium oxide and the like.

The multilayer resin film is a laminated film in which plural resinfilms are layered. Examples of the material for the multilayer resinfilm include the same material as the material for the resin layer(resin film) in the multilayer laminated film. The number of laminationsof resin films in the multilayer resin film is greater than or equal to2, may be greater than or equal to 3, and may be greater than or equalto 5. The number of laminations of resin films in the multilayer resinfilm may be less than or equal to 1000, may be less than or equal to100, and may be less than or equal to 50.

The multilayer resin film may be a multilayer resin film in which two ormore kinds of thermoplastic resin layers having a different opticalproperty (refractive index) are alternately or randomly layered in anarbitrary number of layers. Such a multilayer resin film is constitutedso that desired infrared ray reflecting performance is attained.

Examples of the liquid crystal film include a film prepared by layeringcholesteric liquid crystal layers which reflect light with an arbitrarywavelength in an arbitrary number of layers. Such a liquid crystal filmis constituted so that desired infrared ray reflecting performance isattained.

The infrared ray transmittance in the wavelength of 780 to 2100 nm ofthe first resin layer is higher by 10% or more than the infrared raytransmittance in the wavelength of 780 to 2100 nm of the second resinlayer. Accordingly, considering from a different point of view, theinfrared ray absorptance of the first resin layer is lower than theinfrared ray absorptance of the second resin layer.

Laminated glass prepared with an interlayer film has hitherto beensometimes low in heat shielding properties and sometimes high in Tts(Total solar energy transmitted through a glazing). Furthermore, withregard to the conventional laminated glass, there is a problem thatachieving both low Tts and high visible light transmittance (VisibleTransmittance) at the same time is difficult.

In contrast, since the interlayer film for laminated glass according tothe present invention is provided with the infrared ray reflectionlayer, and furthermore, first and second resin layers are arranged onboth sides of the infrared ray reflection layer and the infrared raytransmittance of the first resin layer is higher than the infrared raytransmittance of the second resin layer, it is possible to enhance theheat shielding properties of laminated glass prepared with theinterlayer film for laminated glass according to the present invention.Furthermore, it is possible to enhance the visible light transmittanceof laminated glass prepared with the interlayer film for laminated glassaccording to the present invention. In the present invention, it ispossible to obtain laminated glass which is low in Tts serving as anindex of heat shielding properties, and furthermore, it is possible toobtain laminated glass which is high in visible light transmittance asdescribed above. For example, it is possible to make the Tts oflaminated glass less than or equal to 60% and make the visible lighttransmittance greater than or equal to 65%. Furthermore, it is alsopossible to make the Tts less than or equal to 55%, it is also possibleto make the Tts less than or equal to 50%, and furthermore, it ispossible to make the visible light transmittance greater than or equalto 70%.

Moreover, since the interlayer film for laminated glass according to thepresent invention is provided with the above-described configuration, itis possible to obtain laminated glass which is low in Tds (direct solarenergy transmitted through a glazing) serving as an index of heatshielding properties. For example, it is possible to make the Tds oflaminated glass less than or equal to 50%, it is also possible to makethe Tds less than or equal to 45%, it is also possible to make the Tdsless than or equal to 41%, and furthermore, it is possible to make theTds less than or equal to 40%.

The first resin layer transmits a relatively large quantity of infraredrays. As such, most of the infrared rays transmitted through the firstresin layer reach the infrared ray reflection layer. Since the infraredray reflection layer reflects infrared rays, infrared rays which havereached the infrared ray reflection layer are reflected by the infraredray reflection layer. Moreover, because the infrared ray transmittanceof the first resin layer is high, most of the infrared rays reflected bythe infrared ray reflection layer are transmitted through the firstresin layer. As a result, a rise in the temperature of an interlayerfilm at the time when infrared rays are made incident into theinterlayer film can be suppressed. As such, the heat shieldingproperties of the interlayer film for laminated glass according to thepresent invention are enhanced, and furthermore, high visible lighttransmittance can be maintained over a long period of time since theinterlayer film for laminated glass is excellent in light resistance.Moreover, by fitting laminated glass prepared with the interlayer filmfor laminated glass according to the present invention into an openingpart of a building or a vehicle, a rise in the temperature of an innerspace of a building or a vehicle can be effectively suppressed.

On the other hand, if the first resin layer and the infrared rayreflection layer transmit a part of infrared rays at all, thetransmitted infrared rays reach the second resin layer. Since theinfrared ray transmittance of the second resin layer is relatively low,the second resin layer effectively cuts off the transmission of infraredrays. As such, the quantity of heat rays passing through the wholeinterlayer film can be reduced. This also enables the heat shieldingproperties of the interlayer film for laminated glass according to thepresent invention to be enhanced, and by fitting laminated glassprepared with the interlayer film for laminated glass according to thepresent invention into an opening part of a building or a vehicle, arise in the temperature of an inner space of a building or a vehicle canbe effectively suppressed.

Moreover, as a result of allowing the quantity of infrared rays whichreach the second resin layer to be reduced, the deterioration of thesecond resin layer can be suppressed and the light resistance of theinterlayer film as a whole is enhanced. As such, high visible lighttransmittance can be maintained over a long period of time. Furthermore,in the case where the second resin layer contains a heat shieldingcompound such as heat shielding particles, the deterioration of the heatshielding compound can also be suppressed and high heat shieldingproperties can be maintained over a long period of time.

Since the infrared ray transmittance in the wavelength of 780 to 2100 nmof the first resin layer is higher by 10% or more than the infrared raytransmittance in the wavelength of 780 to 2100 nm of the second resinlayer, it is preferred that the first resin layer and the second resinlayer be different from each other in composition. In this connection,even when the first resin layer and the second resin layer are the sameas each other in composition, by making the thickness of the first resinlayer thinner than the thickness of the second resin layer, it ispossible to make the infrared ray transmittance in the wavelength of 780to 2100 nm of the first resin layer higher than the infrared raytransmittance in the wavelength of 780 to 2100 nm of the second resinlayer.

When the infrared ray transmittance in the wavelength of 780 to 2100 nmof the first resin layer is defined as Tx1 and the infrared raytransmittance in the wavelength of 780 to 2100 nm of the second resinlayer is defined as Tx2, Tx1 is higher by 10% or more than Tx2. Becausethe heat shielding properties of laminated glass are further enhanced,it is preferred that Tx1 be higher by 20% or more than Tx2, it is morepreferred that Tx1 be higher by 25% or more than Tx2 and it is furtherpreferred that Tx1 be higher by 30% or more than Tx2. Although the upperlimit of a value of (Tx1-Tx2) is not particularly limited, because thetransparency of laminated glass is further enhanced, it is preferredthat (Tx1-Tx2) be less than or equal to 70%, it is more preferred that(Tx1-Tx2) be less than or equal to 60%, it is further preferred that(Tx1-Tx2) be less than or equal to 50% and it is especially preferredthat (Tx1-Tx2) be less than or equal to 40%. For the purpose of furtherenhancing the heat shielding properties and transparency of laminatedglass, the preferred lower limit of Tx1 is 60%, the preferred upperlimit thereof is 90%, the more preferred lower limit thereof is 65%, themore preferred upper limit thereof is 85%, the further preferred lowerlimit thereof is 70%, the further preferred upper limit thereof is 80%and the especially preferred lower limit thereof is 75%. Moreover, forthe purpose of further enhancing the heat shielding properties andtransparency of laminated glass, the preferred lower limit of Tx2 is18%, the more preferred lower limit thereof is 20%, the preferred upperlimit thereof is 75%, the further preferred lower limit thereof is 25%,the more preferred upper limit thereof is 65%, the especially preferredlower limit thereof is 30%, the further preferred upper limit thereof is55%, the most preferred lower limit thereof is 35% and the especiallypreferred upper limit thereof is 50%.

In this connection, the infrared ray transmittance Tx1 or Tx2 in thewavelength of 780 to 2100 nm of the first resin layer or the secondresin layer is measured in the following manner.

A first resin layer or a second resin layer is interposed between twosheets of clear glass (2.5 mm in thickness) to prepare laminated glass.Weighting factors in the range of 780 to 2100 nm among weighting factorsin the range of 300 to 2100 nm shown in Appendix Table 2 in JIS R3106(1998) are used, and each of weighting factors in the range of 780 to2100 nm is divided by the total value of weighting factors in the rangeof 780 to 2100 nm to obtain a newly normalized weighting factor of theinfrared ray transmittance in the range of 780 to 2100 nm. Then, thespectral transmittance in the wavelength of 780 to 2100 nm of a sheet oflaminated glass is obtained in accordance with JIS R3106 (1998) using aspectrophotometer (“U-4100” available from Hitachi High-TechnologiesCorporation). The spectral transmittance obtained is multiplied by thenewly normalized weighting factor to calculate the infrared raytransmittance Tx1 or Tx2 in the wavelength of 780 to 2100 nm as aweighted average.

The first resin layer contains a thermoplastic resin. It is morepreferred that the thermoplastic resin in the first resin layer be apolyvinyl acetal resin. It is preferred that the first resin layercontain a plasticizer, and it is more preferred that the first resinlayer contain a polyvinyl acetal resin and a plasticizer. It ispreferred that the first resin layer contain an ultraviolet rayshielding agent, and it is preferred that the first resin layer containan oxidation inhibitor.

The second resin layer contains a thermoplastic resin. It is morepreferred that the thermoplastic resin in the second resin layer be apolyvinyl acetal resin. It is preferred that the second resin layercontain a plasticizer, and it is more preferred that the second resinlayer contain a polyvinyl acetal resin and a plasticizer. It ispreferred that the second resin layer contain an ultraviolet rayshielding agent, and it is preferred that the second resin layer containan oxidation inhibitor.

It is preferred that the second resin layer contain a heat shieldingcompound. By allowing the heat shielding compound to be contained in thesecond resin layer, the infrared ray transmittance of the first resinlayer becomes higher than the infrared ray transmittance of the secondresin layer. The first resin layer may contain a heat shieldingcompound. Moreover, when the content (% by weight) of the heat shieldingcompound in the first resin layer is smaller than the content (% byweight) of the heat shielding compound in the second resin layer, it iseasy to make the infrared ray transmittance of the first resin layerhigher than the infrared ray transmittance of the second resin layer.Examples of the heat shielding compound include heat shielding particlessuch as metal oxide particles, at least one kind of ingredient among aphthalocyanine compound, a naphthalocyanine compound and ananthracyanine compound (hereinafter, sometimes referred to as IngredientX), and the like. In this connection, the heat shielding compound meansa compound capable of absorbing infrared rays. In the case where aplurality of heat shielding compounds are contained in the first resinlayer or the second resin layer, the total content (% by weight) of theheat shielding compound in the first resin layer is preferably smallerthan the total content (% by weight) of the heat shielding compound inthe second resin layer, more preferably smaller by 0.05% by weight ormore, further preferably smaller by 0.1% by weight or more, especiallypreferably smaller by 0.2% by weight or more and most preferably smallerby 0.4% by weight or more. Furthermore, because the heat shieldingproperties are further enhanced, it is preferred that the differencebetween the total content (% by weight) of the heat shielding compoundin the second resin layer and the total content (% by weight) of theheat shielding compound in the first resin layer be less than or equalto 2% by weight.

Hereinafter, the details of materials constituting the first and secondresin layers will be described.

(Thermoplastic Resin)

The first and second resin layers contain a thermoplastic resin. Thethermoplastic resin is not particularly limited. As the thermoplasticresin, a conventionally known thermoplastic resin can be used. One kindof the thermoplastic resin may be used alone, and two or more kindsthereof may be used in combination. The thermoplastic resin in the firstresin layer and the thermoplastic resin in the second resin layer may bethe same as or different from each other.

Examples of the thermoplastic resin include a polyvinyl acetal resin, anethylene-vinyl acetate copolymer resin, an ethylene-acrylic acidcopolymer resin, a polyurethane resin, a polyvinyl alcohol resin, andthe like. Thermoplastic resins other than these may be used.

It is preferred that the thermoplastic resin be a polyvinyl acetalresin. By using a polyvinyl acetal resin and a plasticizer together, theadhesive force of each of the first and second resin layers to alaminated glass member and another layer such as an infrared rayreflection layer is further enhanced.

For example, the polyvinyl acetal resin can be produced by acetalizingpolyvinyl alcohol with an aldehyde. For example, the polyvinyl alcoholcan be produced by saponifying polyvinyl acetate. The saponificationdegree of the polyvinyl alcohol generally lies within the range of 70 to99.8% by mole.

The average polymerization degree of the polyvinyl alcohol is preferablygreater than or equal to 200, more preferably greater than or equal to500, preferably less than or equal to 5000, more preferably less than orequal to 4000, further preferably less than or equal to 3500, especiallypreferably less than or equal to 3000 and most preferably less than orequal to 2500. When the average polymerization degree is greater than orequal to the above lower limit, the penetration resistance of laminatedglass is further enhanced. When the average polymerization degree isless than or equal to the above upper limit, formation of an interlayerfilm is facilitated. In this connection, the average polymerizationdegree of the polyvinyl alcohol is determined by a method in accordancewith JIS K6726 “Testing methods for polyvinyl alcohol”.

The number of carbon atoms of the acetal group contained in thepolyvinyl acetal resin is not particularly limited. The aldehyde used atthe time of producing the polyvinyl acetal resin is not particularlylimited. It is preferred that the number of carbon atoms of the acetalgroup in the polyvinyl acetal resin be 3 or 4. When the number of carbonatoms of the acetal group in the polyvinyl acetal resin is greater thanor equal to 3, the glass transition temperature of the interlayer filmis sufficiently lowered.

The aldehyde is not particularly limited. In general, an aldehyde with 1to 10 carbon atoms is suitably used as the above-mentioned aldehyde.Examples of the aldehyde with 1 to carbon atoms include propionaldehyde,n-butyraldehyde, isobutyraldehyde, n-valeraldehyde,2-ethylbutyraldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde,n-decylaldehyde, formaldehyde, acetaldehyde, benzaldehyde, and the like.Of these, propionaldehyde, n-butyraldehyde, isobutyraldehyde,n-hexylaldehyde or n-valeraldehyde is preferred, propionaldehyde,n-butyraldehyde or isobutyraldehyde is more preferred, andn-butyraldehyde is further preferred. One kind of the aldehyde may beused alone, and two or more kinds thereof may be used in combination.

The content ratio of the hydroxyl group (the amount of hydroxyl groups)of the polyvinyl acetal resin is preferably greater than or equal to 15%by mole, more preferably greater than or equal to 18% by mole, furtherpreferably greater than or equal to 20% by mole, especially preferablygreater than or equal to 28% by mole, preferably less than or equal to40% by mole, more preferably less than or equal to 35% by mole andfurther preferably less than or equal to 32% by mole. When the contentratio of the hydroxyl group is greater than or equal to the above lowerlimit, the adhesive force of the interlayer film is further enhanced.Moreover, when the content ratio of the hydroxyl group is less than orequal to the above upper limit, the flexibility of the interlayer filmis enhanced and the handling of the interlayer film is facilitated.

The content ratio of the hydroxyl group of the polyvinyl acetal resin isa value expressing the mole fraction determined by dividing the amountof ethylene groups to which the hydroxyl group is bonded by the totalamount of ethylene groups in the main chain in terms of percentage. Forexample, the amount of ethylene groups to which the hydroxyl group isbonded can be measured in accordance with JIS K6726 “Testing methods forpolyvinyl alcohol” to be determined.

The acetylation degree (the amount of acetyl groups) of the polyvinylacetal resin is preferably greater than or equal to 0.1% by mole, morepreferably greater than or equal to 0.3% by mole, further preferablygreater than or equal to 0.5% by mole, preferably less than or equal to30% by mole, more preferably less than or equal to 25% by mole, furtherpreferably less than or equal to 20% by mole, especially preferably lessthan or equal to 15% by mole and most preferably less than or equal to3% by mole. When the acetylation degree is greater than or equal to theabove lower limit, the compatibility between the polyvinyl acetal resinand a plasticizer is enhanced. When the acetylation degree is less thanor equal to the above upper limit, with regard to the interlayer filmand laminated glass, the moisture resistance thereof is enhanced.

The acetylation degree is a molar fraction, represented in percentage,obtained by dividing a value obtained by subtracting the amount ofethylene groups to which the acetal group is bonded and the amount ofethylene groups to which the hydroxyl group is bonded from the totalamount of ethylene groups in the main chain by the total amount ofethylene groups in the main chain. For example, the amount of ethylenegroups to which the acetal group is bonded can be measured in accordancewith JIS K6728 “Testing methods for polyvinyl butyral”.

The acetalization degree of the polyvinyl acetal resin (thebutyralization degree in the case of a polyvinyl butyral resin) ispreferably greater than or equal to 60% by mole, more preferably greaterthan or equal to 63% by mole, preferably less than or equal to 85% bymole, more preferably less than or equal to 75% by mole and furtherpreferably less than or equal to 70% by mole. When the acetalizationdegree is greater than or equal to the above lower limit, thecompatibility between the polyvinyl acetal resin and a plasticizer isenhanced. When the acetalization degree is less than or equal to theabove upper limit, the reaction time required for producing thepolyvinyl acetal resin is shortened.

The acetalization degree is a molar fraction, represented in percentage,obtained by dividing the amount of ethylene groups to which the acetalgroup is bonded by the total amount of ethylene groups in the mainchain.

The acetalization degree can be calculated by a method in accordancewith JIS K6728 “Testing methods for polyvinyl butyral”.

In this connection, it is preferred that the content ratio of thehydroxyl group (the amount of hydroxyl groups), the acetalization degree(the butyralization degree) and the acetylation degree be calculatedfrom the results measured by a method in accordance with JIS K6728“Testing methods for polyvinyl butyral”. In the case where the polyvinylacetal resin is a polyvinyl butyral resin, it is preferred that thecontent ratio of the hydroxyl group (the amount of hydroxyl groups), theacetalization degree (the butyralization degree) and the acetylationdegree be calculated from the results measured by a method in accordancewith JIS K6728 “Testing methods for polyvinyl butyral”.

(Plasticizer)

From the viewpoint of further enhancing the adhesive force of aninterlayer film, it is preferred that the first resin layer contain aplasticizer, and it is preferred that the second resin layer contain aplasticizer. In the case where the thermoplastic resin in each of thefirst and second resin layers is a polyvinyl acetal resin, it isespecially preferred that each of the first and second resin layerscontain a plasticizer.

The plasticizer is not particularly limited. As the plasticizer, aconventionally known plasticizer can be used. One kind of theplasticizer may be used alone, and two or more kinds thereof may be usedin combination.

Examples of the plasticizer include organic ester plasticizers such as amonobasic organic acid ester and a polybasic organic acid ester,phosphate plasticizers such as an organic phosphate plasticizer and anorganic phosphite plasticizer, and the like. Of these, organic esterplasticizers are preferred. It is preferred that the plasticizer be aliquid plasticizer.

The monobasic organic acid ester is not particularly limited andexamples thereof include a glycol ester obtained by the reaction of aglycol and a monobasic organic acid, an ester of triethylene glycol ortripropylene glycol and a monobasic organic acid, and the like. Examplesof the glycol include triethylene glycol, tetraethylene glycol,tripropylene glycol, and the like. Examples of the monobasic organicacid include butyric acid, isobutyric acid, caproic acid, 2-ethylbutyricacid, hepthylic acid, n-octylic acid, 2-ethylhexanoic acid, n-nonylicacid, decylic acid, and the like.

The polybasic organic acid ester is not particularly limited andexamples thereof include an ester compound of a polybasic organic acidand an alcohol having a linear or branched structure of 4 to 8 carbonatoms. Examples of the polybasic organic acid include adipic acid,sebacic acid, azelaic acid and the like.

The organic ester plasticizer is not particularly limited and examplesthereof include triethylene glycol di-2-ethylbutyrate, triethyleneglycol di-2-ethylhexanoate, triethylene glycol dicaprylate, triethyleneglycol di-n-octanoate, triethylene glycol di-n-heptanoate, tetraethyleneglycol di-n-heptanoate, dibutyl sebacate, dioctyl azelate, dibutylcarbitol adipate, ethylene glycol di-2-ethylbutyrate, 1,3-propyleneglycol di-2-ethylbutyrate, 1,4-butylene glycol di-2-ethylbutyrate,diethylene glycol di-2-ethylbutyrate, diethylene glycoldi-2-ethylhexanoate, dipropylene glycol di-2-ethylbutyrate, triethyleneglycol di-2-ethylpentanoate, tetraethylene glycol di-2-ethylbutyrate,diethylene glycol dicaprylate, dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, a mixture of heptyl adipate and nonyl adipate,diisononyl adipate, diisodecyl adipate, heptyl nonyl adipate, dibutylsebacate, oil-modified sebacic acid alkyd, a mixture of a phosphoricacid ester and an adipic acid ester, and the like. Organic esterplasticizers other than these may be used.

The organic phosphate plasticizer is not particularly limited andexamples thereof include tributoxyethyl phosphate, isodecyl phenylphosphate, triisopropyl phosphate and the like.

It is preferred that the plasticizer be a diester plasticizerrepresented by the following formula (1).

In the foregoing formula (1), R1 and R2 each represent an organic groupwith 2 to 10 carbon atoms, R3 represents an ethylene group, anisopropylene group or an n-propylene group, and p represents an integerof 3 to 10. It is preferred that R1 and R2 in the foregoing formula (1)each be an organic group with 5 to 10 carbon atoms, and it is morepreferred that R1 and R2 each be an organic group with 6 to 10 carbonatoms.

It is preferred that the plasticizer include at least one kind amongtriethylene glycol di-2-ethylhexanoate (3GO) and triethylene glycoldi-2-ethylbutyrate (3GH), and it is more preferred that the plasticizerinclude triethylene glycol di-2-ethylhexanoate.

The content of the plasticizer is not particularly limited. In each ofthe first and second resin layers, relative to 100 parts by weight ofthe thermoplastic resin, the content of the plasticizer is preferablygreater than or equal to 25 parts by weight, more preferably greaterthan or equal to 30 parts by weight, further preferably greater than orequal to 35 parts by weight, preferably less than or equal to 75 partsby weight, more preferably less than or equal to 60 parts by weight,further preferably less than or equal to 50 parts by weight andespecially preferably less than or equal to 40 parts by weight. When thecontent of the plasticizer is greater than or equal to the above lowerlimit, the penetration resistance of laminated glass is furtherenhanced. When the content of the plasticizer is less than or equal tothe above upper limit, the transparency of the interlayer film isfurther enhanced.

(Heat Shielding Compound)

Ingredient X:

It is preferred that the second resin layer contain a heat shieldingcompound. It is preferred that the second resin layer contain at leastone kind of Ingredient X among a phthalocyanine compound, anaphthalocyanine compound and an anthracyanine compound. It is preferredthat the second resin layer contain at least one kind of Ingredient Xamong a phthalocyanine compound, a naphthalocyanine compound and ananthracyanine compound or contain heat shielding particles describedbelow. The first resin layer may contain the Ingredient X. TheIngredient X is a heat shielding compound. By allowing the Ingredient Xto be used in at least one layer among the interlayer film as a whole,infrared rays (heat rays) can be effectively cut off. By allowing theIngredient X to be contained in the second resin layer, infrared rayscan be further effectively cut off.

The Ingredient X is not particularly limited. As the Ingredient X,conventionally known phthalocyanine compound, naphthalocyanine compoundand anthracyanine compound can be used. One kind of the Ingredient X maybe used alone, and two or more kinds thereof may be used in combination.

Examples of the Ingredient X include phthalocyanine, a derivative ofphthalocyanine, naphthalocyanine, a derivative of naphthalocyanine,anthracyanine, a derivative of anthracyanine, and the like. It ispreferred that each of the phthalocyanine compound and the derivative ofphthalocyanine have a phthalocyanine skeleton. It is preferred that eachof the naphthalocyanine compound and the derivative of naphthalocyaninehave a naphthalocyanine skeleton. It is preferred that each of theanthracyanine compound and the derivative of anthracyanine have ananthracyanine skeleton.

From the viewpoint of further enhancing the heat shielding properties ofthe interlayer film and laminated glass, it is preferred that theIngredient X be at least one kind selected from the group consisting ofphthalocyanine, a derivative of phthalocyanine, naphthalocyanine and aderivative of naphthalocyanine, and it is more preferred that theIngredient X be at least one kind among phthalocyanine and a derivativeof phthalocyanine.

From the viewpoints of effectively enhancing the heat shieldingproperties and maintaining the visible light transmittance at a higherlevel over a long period of time, it is preferred that the Ingredient Xcontain vanadium atoms or copper atoms. It is preferred that theIngredient X contain vanadium atoms and it is also preferred that theIngredient X contain copper atoms. It is more preferred that theIngredient X be at least one kind among phthalocyanine containingvanadium atoms or copper atoms and a derivative of phthalocyaninecontaining vanadium atoms or copper atoms. From the viewpoint of stillfurther enhancing the heat shielding properties of the interlayer filmand the laminated glass, it is preferred that the Ingredient X have astructural unit in which an oxygen atom is bonded to a vanadium atom.

In the case where the first resin layer or the second resin layercontains the Ingredient X, in 100% by weight of each of the first andsecond resin layers, the content of the Ingredient X is preferablygreater than or equal to 0.001% by weight, more preferably greater thanor equal to 0.005% by weight, further preferably greater than or equalto 0.01% by weight, especially preferably greater than or equal to 0.02%by weight, preferably less than or equal to 0.2% by weight, morepreferably less than or equal to 0.1% by weight, further preferably lessthan or equal to 0.05% by weight, especially preferably less than orequal to 0.04% by weight and most preferably less than or equal to 0.02%by weight. When the content of the Ingredient X in each of the first andsecond resin layers is greater than or equal to the above lower limitand less than or equal to the above upper limit, the heat shieldingproperties are sufficiently enhanced and the visible light transmittanceis sufficiently enhanced. For example, it is possible to make thevisible light transmittance greater than or equal to 70%,

Heat Shielding Particles:

It is preferred that the second resin layer contain heat shieldingparticles. The first resin layer may contain heat shielding particles.The heat shielding particle is a heat shielding compound. By allowing aheat shielding compound to be used in at least one layer among theinterlayer film as a whole, infrared rays (heat rays) can be effectivelycut off. By allowing heat shielding particles to be contained in thesecond resin layer, infrared rays can be further effectively cut off.

From the viewpoint of further enhancing the heat shielding properties oflaminated glass, it is more preferred that the heat shielding particlesbe metal oxide particles. It is preferred that the heat shieldingparticle be a particle (a metal oxide particle) formed from an oxide ofa metal. One kind of the heat shielding particles may be used alone, andtwo or more kinds thereof may be used in combination.

The energy amount of an infrared ray with a wavelength greater than orequal to 780 nm which is longer than that of visible light is small ascompared with an ultraviolet ray. However, the thermal action ofinfrared rays is large, and once infrared rays are absorbed into asubstance, heat is released from the substance. As such, infrared raysare generally called heat rays. By the use of the heat shieldingparticles, infrared rays (heat rays) can be effectively cut off. In thisconnection, the heat shielding particle means a particle capable ofabsorbing infrared rays.

Specific examples of the heat shielding particles include metal oxideparticles such as aluminum-doped tin oxide particles, indium-doped tinoxide particles, antimony-doped tin oxide particles (ATO particles),gallium-doped zinc oxide particles (GZO particles), indium-doped zincoxide particles (IZO particles), aluminum-doped zinc oxide particles(AZO particles), niobium-doped titanium oxide particles, sodium-dopedtungsten oxide particles, cesium-doped tungsten oxide particles,thallium-doped tungsten oxide particles, rubidium-doped tungsten oxideparticles, tin-doped indium oxide particles (ITO particles), tin-dopedzinc oxide particles and silicon-doped zinc oxide particles, lanthanumhexaboride (LaB₆) particles, and the like. Heat shielding particlesother than these may be used. Of these, since the heat ray shieldingfunction is high, preferred are metal oxide particles, more preferredare ATO particles, GZO particles, IZO particles, ITO particles ortungsten oxide particles, and especially preferred are ITO particles ortungsten oxide particles. In particular, since the heat ray shieldingfunction is high and the particles are readily available, preferred aretin-doped indium oxide particles (ITO particles), and also preferred aretungsten oxide particles.

The tungsten oxide particles are generally represented by the followingformula (X1) or the following formula (X2). In the interlayer film forlaminated glass according to the present invention, the tungsten oxideparticles represented by the following formula (X1) or the followingformula (X2) are suitably used.

W_(y)O_(z)  Formula (X1)

In the foregoing formula (X1), W represents tungsten, 0 representsoxygen, and y and z satisfy the relation of 2.0<z/y<3.0.

M_(x)W_(y)O_(z)  Formula (X2)

In the foregoing formula (X2), M represents at least one kind of elementselected from the group consisting of H, He, an alkali metal, analkaline earth metal, a rare earth element, Mg, Zr, Cr, Mn Fe, Ru, Co,Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, Si, Ge, Sn, Pb,Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta and Re, W representstungsten, O represents oxygen, and x, y and z satisfy the relations of0.001≤x/y≤1 and 2.0<z/y≤3.0.

From the viewpoint of further enhancing the heat shielding properties ofthe interlayer film and laminated glass, it is preferred that thetungsten oxide particles be metal-doped tungsten oxide particles.Examples of the “tungsten oxide particles” include metal-doped tungstenoxide particles. Specifically, examples of the metal-doped tungstenoxide particles include sodium-doped tungsten oxide particles,cesium-doped tungsten oxide particles, thallium-doped tungsten oxideparticles, rubidium-doped tungsten oxide particles, and the like.

From the viewpoint of further enhancing the heat shielding properties ofthe interlayer film and laminated glass, cesium-doped tungsten oxideparticles are especially preferred. From the viewpoint of still furtherenhancing the heat shielding properties of the interlayer film andlaminated glass, it is preferred that the cesium-doped tungsten oxideparticles be tungsten oxide particles represented by the formula:Cs_(0.33)WO₃.

The average particle diameter of the heat shielding particles ispreferably greater than or equal to 0.01 μm, more preferably greaterthan or equal to 0.02 μm, preferably less than or equal to 0.1 μm andmore preferably less than or equal to 0.05 μm. When the average particlediameter is greater than or equal to the above lower limit, the heat rayshielding properties are sufficiently enhanced. When the averageparticle diameter is less than or equal to the above upper limit, thedispersibility of heat shielding particles is enhanced.

The “average particle diameter” refers to the volume average particlediameter. The average particle diameter can be measured using a particlesize distribution measuring apparatus (“UPA-EX150” available fromNIKKISO CO., LTD.), or the like.

In the case where the first resin layer or the second resin layercontains the heat shielding particles, in 100% by weight of each of thefirst and second resin layers, the content of the heat shieldingparticles is preferably greater than or equal to 0.01% by weight, morepreferably greater than or equal to 0.1% by weight, further preferablygreater than or equal to 1% by weight, especially preferably greaterthan or equal to 1.5% by weight, preferably less than or equal to 6% byweight, more preferably less than or equal to 5.5% by weight, furtherpreferably less than or equal to 4% by weight, especially preferablyless than or equal to 3.5% by weight and most preferably less than orequal to 3.0% by weight. When the content of the heat shieldingparticles is greater than or equal to the above lower limit and lessthan or equal to the above upper limit, the heat shielding propertiesare sufficiently enhanced and the visible light transmittance issufficiently enhanced.

In the case where the first resin layer or the second resin layercontains the heat shielding particles, it is preferred that each of thefirst and second resin layers contain the heat shielding particles in aproportion greater than or equal to 0.1 g/m² and less than or equal to12 g/m². In the case where the proportion of the heat shieldingparticles lies within the above-mentioned range, the heat shieldingproperties are sufficiently enhanced and the visible light transmittanceis sufficiently enhanced. The proportion of the heat shielding particlesis preferably greater than or equal to 0.5 g/m², more preferably greaterthan or equal to 0.8 g/m², further preferably greater than or equal to1.5 g/m², especially preferably greater than or equal to 3 g/m²,preferably less than or equal to 11 g/m², more preferably less than orequal to 10 g/m², further preferably less than or equal to 9 g/m² andespecially preferably less than or equal to 7 g/m². When the proportionis greater than or equal to the above lower limit, the heat shieldingproperties are further enhanced. When the proportion is less than orequal to the above upper limit, the visible light transmittance isfurther enhanced.

(Ultraviolet Ray Shielding Agent)

It is preferred that the first resin layer contain an ultraviolet rayshielding agent. It is preferred that the second resin layer contain anultraviolet ray shielding agent. It is more preferred that both of thefirst resin layer and the second resin layer contain an ultraviolet rayshielding agent. By the use of an ultraviolet ray shielding agent, evenwhen the interlayer film and the laminated glass are used for a longperiod of time, the visible light transmittance becomes furtherdifficult to be lowered. One kind of the ultraviolet ray shielding agentmay be used alone, and two or more kinds thereof may be used incombination.

The ultraviolet ray shielding agent includes an ultraviolet rayabsorber. It is preferred that the ultraviolet ray shielding agent be anultraviolet ray absorber.

Examples of a common ultraviolet ray shielding agent which is heretoforewidely known include a metal-based ultraviolet ray shielding agent, ametal oxide-based ultraviolet ray shielding agent, a benzotriazole-basedultraviolet ray shielding agent (a benzotriazole compound), abenzophenone-based ultraviolet ray shielding agent (a benzophenonecompound), a triazine-based ultraviolet ray shielding agent (a triazinecompound), a malonic acid ester-based ultraviolet ray shielding agent (amalonic acid ester compound), an oxanilide-based ultraviolet rayshielding agent (an oxanilide compound), a benzoate-based ultravioletray shielding agent (a benzoate compound) and the like.

Examples of the metal-based ultraviolet ray shielding agent includeplatinum particles, particles in which the surface of platinum particlesis coated with silica, palladium particles, particles in which thesurface of palladium particles is coated with silica, and the like. Itis preferred that the ultraviolet ray shielding agent not be heatshielding particles.

Examples of the metal oxide-based ultraviolet ray shielding agentinclude zinc oxide, titanium oxide, cerium oxide and the like.Furthermore, as the metal oxide-based ultraviolet ray shielding agent,the surface thereof may be coated. Examples of a coating material forthe surface of the metal oxide-based ultraviolet ray shielding agentinclude an insulating metal oxide, a hydrolyzable organosiliconcompound, a silicone compound and the like.

Examples of the insulating metal oxide include silica, alumina, zirconiaand the like. For example, the insulating metal oxide has a band-gapenergy greater than or equal to 5.0 eV.

Examples of the benzotriazole-based ultraviolet ray shielding agentinclude benzotriazole-based ultraviolet ray shielding agents such as2-(2′-hydroxy-5′-methylphenyl)benzotriazole (“Tinuvin P” available fromBASF Japan Ltd.), 2-(2′-hydroxy-3′,5′-di-t-butylphenyl)benzotriazole(“Tinuvin 320” available from BASF Japan Ltd.),2-(2′-hydroxy-3′-t-butyl-5-methylphenyl)-5-chlorobenzotriazole (“Tinuvin326” available from BASF Japan Ltd.) and2-(2′-hydroxy-3′,5′-di-amylphenyl)benzotriazole (“Tinuvin 328” availablefrom BASF Japan Ltd.). It is preferred that the benzotriazole-basedultraviolet ray shielding agent be a benzotriazole-based ultraviolet rayshielding agent containing halogen atoms, and it is more preferred thatthe ultraviolet ray shielding agent be a benzotriazole-based ultravioletray shielding agent containing chlorine atoms, since those are excellentin ultraviolet ray absorbing performance.

Examples of the benzophenone-based ultraviolet ray shielding agentinclude octabenzone (“Chimassorb 81” available from BASF Japan Ltd.) andthe like.

Examples of the triazine-based ultraviolet ray shielding agent include2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol (“Tinuvin1577FF” available from BASF Japan Ltd.) and the like.

Examples of the malonic acid ester-based ultraviolet ray shielding agentinclude dimethyl-2-(p-methoxybenzylidene)malonate,tetraethyl-2,2-(1,4-phenylenedimethylidyne)bismalonate,2-(p-methoxybenzylidene)-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)malonateand the like.

Examples of a commercial product of the malonic acid ester-basedultraviolet ray shielding agent include Hostavin B-CAP, Hostavin PR-25and Hostavin PR-31 (any of these is available from Clariant Japan K.K.).

Examples of the oxanilide-based ultraviolet ray shielding agent includea kind of oxalic acid diamide having a substituted aryl group and thelike on the nitrogen atom such asN-(2-ethylphenyl)-N′-(2-ethoxy-5-t-butylphenyl)oxalic acid diamide,N-(2-ethylphenyl)-N′-(2-ethoxy-phenyl)oxalic acid diamide and2-ethyl-2′-ethoxy-oxanilide (“Sanduvor VSU” available from ClariantJapan K.K.).

Examples of the benzoate-based ultraviolet ray shielding agent include2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (“Tinuvin120” available from BASF Japan Ltd.) and the like.

With regard to the interlayer film and laminated glass, in order tosuppress the lowering invisible light transmittance thereof after thelapse of time, it is preferred that the ultraviolet ray shielding agentbe 2-(2′-hydroxy-3′-t-butyl-5-methylphenyl)-5-chlorobenzotriazole(“Tinuvin 326” available from BASF Japan Ltd.) or2-(2′-hydroxy-3′,5′-di-amylphenyl)benzotriazole (“Tinuvin 328” availablefrom BASF Japan Ltd.), and the ultraviolet ray shielding agent may be2-(2′-hydroxy-3′-t-butyl-5-methylphenyl)-5-chlorobenzotriazole.

In the case where each of the first and second resin layers contains theultraviolet ray shielding agent, in 100% by weight of each of the firstand second resin layers, the content of the ultraviolet ray shieldingagent is preferably greater than or equal to 0.1% by weight, morepreferably greater than or equal to 0.2% by weight, further preferablygreater than or equal to 0.3% by weight, especially preferably greaterthan or equal to 0.5% by weight, preferably less than or equal to 2.5%by weight, more preferably less than or equal to 2% by weight, furtherpreferably less than or equal to 1% by weight and especially preferablyless than or equal to 0.8% by weight. When the content of theultraviolet ray shielding agent is greater than or equal to the abovelower limit and less than or equal to the above upper limit, thelowering in visible light transmittance after the lapse of time isfurther suppressed. In particular, by allowing the content of theultraviolet ray shielding agent to be greater than or equal to 0.2% byweight in 100% by weight of each of the first and second resin layers,with regard to the interlayer film and laminated glass, the loweringinvisible light transmittance thereof after the lapse of time can besignificantly suppressed. Furthermore, when the content of theultraviolet ray shielding agent in 100% by weight of the second resinlayer is greater than the content of the ultraviolet ray shielding agentin 100% by weight of the first resin layer, with regard to theinterlayer film and laminated glass, the lowering in visible lighttransmittance thereof after the lapse of time can be furthersignificantly suppressed.

(Oxidation Inhibitor)

It is preferred that the first resin layer contain an oxidationinhibitor. It is preferred that the second resin layer contain anoxidation inhibitor. It is preferred that both of the first resin layerand the second resin layer contain an oxidation inhibitor. One kind ofthe oxidation inhibitor may be used alone, and two or more kinds thereofmay be used in combination.

Examples of the oxidation inhibitor include a phenol-based oxidationinhibitor, a sulfur-based oxidation inhibitor, a phosphorus-basedoxidation inhibitor and the like. The phenol-based oxidation inhibitoris an oxidation inhibitor having a phenol skeleton. The sulfur-basedoxidation inhibitor is an oxidation inhibitor containing a sulfur atom.The phosphorus-based oxidation inhibitor is an oxidation inhibitorcontaining a phosphorus atom.

It is preferred that the oxidation inhibitor be a phenol-based oxidationinhibitor or a phosphorus-based oxidation inhibitor.

Examples of the phenol-based oxidation inhibitor include2,6-di-t-butyl-p-cresol (BHT), butylated hydroxyanisole (BHA),2,6-di-t-butyl-4-ethylphenol,stearyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate,2,2′-methylenebis-(4-methyl-6-butylphenol),2,2′-methylenebis-(4-ethyl-6-t-butylphenol),4,4′-butylidene-bis-(3-methyl-6-t-butylphenol),1,1,3-tris-(2-methyl-hydroxy-5-t-butylphenyl)butane,tetrakis[methylene-3-(3′,5′-butyl-4-hydroxyphenyl)propionate]methane,1,3,3-tris-(2-methyl-4-hydroxy-5-t-butylphenol)butane,1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene,bis(3,3′-t-butylphenol)butyric acid glycol ester,bis(3-t-butyl-4-hydroxy-5-methylbenzenepropanoicacid)ethylenebis(oxyethylene), and the like. One kind or two or morekinds among these oxidation inhibitors are suitably used.

Examples of the phosphorus-based oxidation inhibitor include tridecylphosphite, tris(tridecyl) phosphite, triphenyl phosphite, trinonylphenylphosphite, bis(tridecyl)pentaerithritol diphosphite, bis(decyl)pentaerithritol diphosphite, tris(2,4-di-t-butylphenyl)phosphite,bis(2,4-di-t-butyl-6-methylphenyl)ethyl ester phosphorous acid,tris(2,4-di-t-butylphenyl)phosphite,2,2-methylenebis(4,6-di-t-butyl-1-phenyloxy)(2-ethylhexyloxy)phosphorus, and the like. One kind or two or more kindsamong these oxidation inhibitors are suitably used.

Examples of a commercial product of the oxidation inhibitor include“IRGANOX 245” available from BASF Japan Ltd., “IRGAFOS 168” availablefrom BASF Japan Ltd., “IRGAFOS 38” available from BASF Japan Ltd.,“Sumilizer BHT” available from Sumitomo Chemical Co., Ltd. “Irganox1010” available from Nihon Ciba-Geigy K.K., and the like.

In the case where each of the first and second resin layers contains theoxidation inhibitor, in 100% by weight of each of the first and secondresin layers, the content of the oxidation inhibitor is preferablygreater than or equal to 0.1% by weight, preferably less than or equalto 2% by weight and more preferably less than or equal to 1.8% byweight. When the content of the oxidation inhibitor is greater than orequal to the above lower limit, with regard to the interlayer film andlaminated glass, high visible light transmittance thereof is maintainedover a longer period of time. When the content of the oxidationinhibitor is less than or equal to the above upper limit, an effectcommensurate with the addition of an oxidation inhibitor becomes easy tobe attained.

(Adhesive Force Regulating Agent)

It is preferred that at least one among the first resin layer and thesecond resin layer contain an adhesive force regulating agent. It ispreferred that the first resin layer contain an adhesive forceregulating agent. It is preferred that the second resin layer contain anadhesive force regulating agent. It is more preferred that both of thefirst resin layer and the second resin layer contain an adhesive forceregulating agent. By the use of an adhesive force regulating agent, theadhesivity between the interlayer film and a sheet of glass iscontrolled, and laminated glass which is excellent in penetrationresistance is obtained. Furthermore, by allowing an adhesive forceregulating agent to be contained in the first resin layer and the secondresin layer, in the case where a falling-ball test as the test forpenetration resistance is performed, an effect of enabling glassfragments of laminated glass to become smaller in size is exerted. Inparticular, when the adhesive force regulating agent is a metal salt,glass fragments of laminated glass become further smaller in size. Onekind of the adhesive force regulating agent may be used alone, and twoor more kinds thereof may be used in combination.

The adhesive force regulating agent is not particularly limited, it ispreferred that the adhesive force regulating agent be a metal salt, andit is preferred that the adhesive force regulating agent be at least onekind of metal salt selected from the group consisting of an alkali metalsalt, an alkaline earth metal salt and an Mg salt. It is preferred thatthe metal salt contain at least one kind of metal among K and Mg. It ismore preferred that the metal salt be an alkali metal salt of an organicacid with 2 to 16 carbon atoms or an alkaline earth metal salt of anorganic acid with 2 to 16 carbon atoms, and it is further preferred thatthe metal salt be a magnesium carboxylate with 2 to 16 carbon atoms or apotassium carboxylate with 2 to 16 carbon atoms. Although the magnesiumcarboxylate with 2 to 16 carbon atoms and the potassium carboxylate with2 to 16 carbon atoms are not particularly limited, examples thereofinclude magnesium acetate, potassium acetate, magnesium propionate,potassium propionate, magnesium 2-ethylbutanoate, potassium2-ethylbutanoate, magnesium 2-ethylhexanoate, potassium2-ethylhexanoate, and the like.

The content of the adhesive force regulating agent is not particularlylimited. In each of the first resin layer and the second resin layer,with regard to the content of the adhesive force regulating agentrelative to 100 parts by weight of the thermoplastic resin, thepreferred lower limit is 0.0005 part by weight and the preferred upperlimit is 0.05 part by weight. When the content of the adhesive forceregulating agent is greater than or equal to 0.0005 part by weight, thepenetration resistance of laminated glass is enhanced. When the contentof the adhesive force regulating agent is less than or equal to 0.05part by weight, the transparency of the interlayer film for laminatedglass is further enhanced. The more preferred lower limit of the contentof the adhesive force regulating agent is 0.002 part by weight and themore preferred upper limit thereof is 0.02 part by weight. Moreover, ina surface layer which is brought into contact with a laminated glassmember in the case where each of the first and second resin layers has atwo or more-layered structure, and in each of the first and second resinlayers in the case where each of the first and second resin layers has asingle-layer structure, with regard to the content of the adhesive forceregulating agent relative to 100 parts by weight of the thermoplasticresin, the preferred lower limit is 0.0005 part by weight and thepreferred upper limit is 0.05 part by weight.

Because the moisture resistance of the first resin layer is enhanced, itis preferred that the total of the contents of the alkali metal, thealkaline earth metal and Mg in each of the first and second resin layersbe less than or equal to 300 ppm. For example, the alkali metal, thealkaline earth metal and Mg may be contained as metals derived from anadhesive force regulating agent mentioned above and may be contained asmetals derived from a neutralizing agent used at the time ofsynthesizing a polyvinyl acetal resin. It is more preferred that thetotal of the contents of the alkali metal, the alkaline earth metal andMg in each of the first and second resin layers be less than or equal to200 ppm, it is further preferred that the total thereof be less than orequal to 150 ppm, and it is especially preferred that the total thereofbe less than or equal to 100 ppm. Moreover, in a surface layer which isbrought into contact with a laminated glass member in the case whereeach of the first and second resin layers has a two or more-layeredstructure, and in each of the first and second resin layers in the casewhere each of the first and second resin layers has a single-layerstructure, it is preferred that the total of the contents of the alkalimetal, the alkaline earth metal and Mg be less than or equal to 300 ppm,it is more preferred that the total thereof be less than or equal to 200ppm, it is further preferred that the total thereof be less than orequal to 150 ppm, and it is especially preferred that the total thereofbe less than or equal to 100 ppm. Moreover, in a surface layer which isbrought into contact with a laminated glass member in the case whereeach of the first and second resin layers has a two or more-layeredstructure, and in each of the first and second resin layers in the casewhere each of the first and second resin layers has a single-layerstructure, it is preferred that the total content of Mg be less than orequal to 300 ppm, it is more preferred that the content thereof be lessthan or equal to 200 ppm, it is further preferred that the contentthereof be less than or equal to 150 ppm, and it is especially preferredthat the content thereof be less than or equal to 100 ppm.

(Other Ingredients)

The interlayer film for laminated glass according to the presentinvention may include additives such as a light stabilizer, a flameretardant, an antistatic agent, a pigment, a dye, a moisture-resistanceimproving agent and a fluorescent brightening agent, as necessary. Onekind of these additives may be used alone, and two or more kinds thereofmay be used in combination.

(Other Details of Interlayer Film for Laminated Glass)

It is preferred that the interlayer film for laminated glass accordingto the present invention be arranged between a first laminated glassmember and a second laminated glass member to be used.

It is preferred that the interlayer film for laminated glass accordingto the present invention be used for obtaining laminated glass which isfitted into an opening part between an outer space (first space) and aninner space (second space) into which heat rays are made incident fromthe outer space for a building or a vehicle. In this case, it ispreferred that, among the first and second resin layers, the first resinlayer be arranged so as to be positioned at the outer space side.

The thickness of the interlayer film for laminated glass according tothe present invention is not particularly limited. From the viewpoint ofthe practical aspect and the viewpoint of sufficiently enhancing theheat shielding properties, the thickness of the interlayer film ispreferably greater than or equal to 0.1 mm, more preferably greater thanor equal to 0.25 mm, preferably less than or equal to 3 mm and morepreferably less than or equal to 1.5 mm. When the thickness of theinterlayer film is greater than or equal to the above lower limit, thepenetration resistance of laminated glass is enhanced.

The thickness of the infrared ray reflection layer is preferably greaterthan or equal to 0.01 mm, more preferably greater than or equal to 0.04mm, further preferably greater than or equal to 0.07 mm, preferably lessthan or equal to 0.3 mm, more preferably less than or equal to 0.2 mm,further preferably less than or equal to 0.18 mm and especiallypreferably less than or equal to 0.16 mm. When the thickness of theinfrared ray reflection layer is greater than or equal to the abovelower limit, the heat shielding properties of laminated glass arefurther enhanced. When the thickness of the infrared ray reflectionlayer is less than or equal to the above upper limit, the transparencyof laminated glass is further enhanced.

The thickness of each of the first and second resin layers is preferablygreater than or equal to 0.1 mm, more preferably greater than or equalto 0.2 mm, further preferably greater than or equal to 0.25 mm,especially preferably greater than or equal to 0.3 mm, preferably lessthan or equal to 1.0 mm, more preferably less than or equal to 0.6 mm,still more preferably less than or equal to 0.5 mm, further preferablyless than or equal to 0.45 mm and especially preferably less than orequal to 0.4 mm. When the thickness of the first or second resin layeris greater than or equal to the above lower limit, the penetrationresistance of laminated glass is further enhanced. When the thickness ofthe first or second resin layer is less than or equal to the above upperlimit, the transparency of laminated glass is further enhanced.

The production method of the interlayer film for laminated glassaccording to the present invention is not particularly limited. As theproduction method of the interlayer film, a conventionally known methodcan be used. Examples thereof include a production method of kneadingrespective ingredients described above and forming the kneaded productinto an interlayer film, and the like. A production method ofextrusion-molding is preferred because the method is suitable forcontinuous production. In particular, it is preferred that the first andsecond resin layers be formed by extrusion molding.

The method for kneading is not particularly limited. Examples of thismethod include a method using an extruder, a plastograph, a kneader, abanbury mixer, a calender roll, or the like. Of these, a method using anextruder is preferred and a method using a twin screw extruder is morepreferred because the methods are suitable for continuous production.

In this connection, at the time of obtaining the interlayer film forlaminated glass according to the present invention, a first resin layer,an infrared ray reflection layer and a second resin layer are separatelyprepared, after which the first resin layer, the infrared ray reflectionlayer and the second resin layer may be layered to obtain an interlayerfilm, and the layering method is not particularly limited. Examples ofthe layering method include a heat lamination method and the like.

Moreover, a first resin layer, an infrared ray reflection layer and asecond resin layer may be layered by coextrusion to obtain an interlayerfilm. Moreover, a first resin layer and an infrared ray reflection layermay be coextruded to prepare a coextruded product and a second resinlayer may be layered on the infrared ray reflection layer side of thecoextruded product to obtain an interlayer film. A second resin layerand an infrared ray reflection layer may be coextruded to prepare acoextruded product and a first resin layer may be layered on theinfrared ray reflection layer side of the coextruded product to obtainan interlayer film.

Moreover, by allowing compositions for forming first and second resinlayers to be coated on surfaces of the infrared ray reflection layer,the first and second resin layers may be formed to obtain an interlayerfilm.

Because the interlayer film is allowed to be excellent in productionefficiency, it is preferred that respective polyvinyl acetal resinscontained in the first resin layer and the second resin layer be thesame as each other, and it is more preferred that respective polyvinylacetal resins contained therein be the same as each other and respectiveplasticizers contained therein be the same as each other.

(Laminated Glass)

The laminated glass according to the present invention is provided witha first laminated glass member, a second laminated glass member and aninterlayer film arranged between the first and second laminated glassmembers. The interlayer film is the above-described interlayer film forlaminated glass. The first laminated glass member is arranged on theoutside of the first resin layer in the interlayer film for laminatedglass. The second laminated glass member is arranged on the outside ofthe second resin layer in the interlayer film for laminated glass.

It is preferred that the laminated glass according to the presentinvention be laminated glass which is fitted into an opening partbetween an outer space and an inner space into which heat rays are madeincident from the outer space for a building or a vehicle. In this case,it is preferred that, among the first and second laminated glassmembers, the first laminated glass member be arranged so as to bepositioned at the outer space side.

FIG. 2 shows an example of laminated glass prepared with an interlayerfilm for laminated glass in accordance with one embodiment of thepresent invention represented as a sectional view.

Laminated glass 11 shown in FIG. 2 is provided with an interlayer film 1and first and second laminated glass members 21 and 22. The interlayerfilm 1 is sandwiched between the first and second laminated glassmembers 21 and 22. The first laminated glass member 21 is layered on afirst surface 1 a of the interlayer film 1. The second laminated glassmember 22 is layered on a second surface 1 b opposite to the firstsurface 1 a of the interlayer film 1. The first laminated glass member21 is layered on an outer surface 3 a of a first resin layer 3 in theinterlayer film 1. The second laminated glass member 22 is layered on anouter surface 4 a of a second resin layer 4 in the interlayer film 1.

It is preferred that the infrared ray transmittance in the wavelength of780 to 2100 nm of the first laminated glass member be higher than theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond laminated glass member. In this case, the first laminated glassmember transmits a relatively large quantity of infrared rays.Furthermore, most of the infrared rays transmitted through the firstlaminated glass member are also transmitted through the first resinlayer. As such, most of the infrared rays transmitted through the firstlaminated glass member and the first resin layer reach the infrared rayreflection layer. Infrared rays which have reached the infrared rayreflection layer are reflected by the infrared ray reflection layer.Moreover, because the infrared ray transmittance of the first laminatedglass member and the first resin layer is high, most of the infraredrays reflected by the infrared ray reflection layer are transmittedthrough the first resin layer and the first laminated glass member. As aresult, a rise in the temperature of laminated glass at the time wheninfrared rays are made incident into the laminated glass can besuppressed. As such, the heat shielding properties of the laminatedglass are enhanced, and furthermore, high visible light transmittancecan be maintained over a long period of time since the laminated glassis excellent in light resistance. Moreover, by fitting the laminatedglass into an opening part of a building or a vehicle, a rise in thetemperature of an inner space of a building or a vehicle can beeffectively suppressed.

On the other hand, if the first laminated glass member, the first resinlayer and the infrared ray reflection layer transmit a part of infraredrays at all, the transmitted infrared rays reach the second resin layer.Since the infrared ray transmittance of the second resin layer isrelatively low, the second resin layer effectively cuts off thetransmission of infrared rays. Furthermore, since the infrared raytransmittance of the second laminated glass member is also relativelylow, the second laminated glass member effectively cuts off thetransmission of infrared rays. As such, the quantity of heat rayspassing through the laminated glass as a whole can be reduced. This alsoenables the heat shielding properties of laminated glass to be enhanced,and by fitting the laminated glass into an opening part of a building ora vehicle, a rise in the temperature of an inner space of a building ora vehicle can be effectively suppressed.

When the infrared ray transmittance in the wavelength of 780 to 2100 nmof a first laminated glass member is defined as Ty1 and the infrared raytransmittance in the wavelength of 780 to 2100 nm of a second laminatedglass member is defined as Ty2, as mentioned above, it is preferred thatTy1 be higher than Ty2. Because the heat shielding properties oflaminated glass are further enhanced, it is preferred that Ty1 be higherby 10% or more than Ty2, it is more preferred that Ty1 be higher by 15%or more than Ty2 and it is further preferred that Ty1 be higher by 20%or more than Ty2. Although the upper limit of a value of (Ty1-Ty2) isnot particularly limited, because the transparency of laminated glass isfurther enhanced, it is preferred that (Ty1-Ty2) be less than or equalto 50%, it is more preferred that (Ty1-Ty2) be less than or equal to40%, it is further preferred that (Ty1-Ty2) be less than or equal to 30%and it is especially preferred that (Ty1-Ty2) be less than or equal to25%. For the purpose of further enhancing the heat shielding propertiesand transparency of laminated glass, the preferred lower limit of Ty1 is50%, the preferred upper limit thereof is 90%, the more preferred lowerlimit thereof is 55%, the more preferred upper limit thereof is 88%, thefurther preferred lower limit thereof is 60% and the further preferredupper limit thereof is 86%. Moreover, for the purpose of furtherenhancing the heat shielding properties and transparency of laminatedglass, the preferred lower limit of Ty2 is 40%, the preferred upperlimit thereof is 88%, the more preferred lower limit thereof is 45%, themore preferred upper limit thereof is 86%, the further preferred lowerlimit thereof is 55%, the further preferred upper limit thereof is 70%,the especially preferred lower limit thereof is 60% and the especiallypreferred upper limit thereof is 65%.

When the infrared ray transmittance in the wavelength of 780 to 2100 nmof the whole layer composed of a first laminated glass member and afirst resin layer is defined as T1 and the infrared ray transmittance inthe wavelength of 780 to 2100 nm of the whole layer composed of a secondlaminated glass member and a second resin layer is defined as T2, it ispreferred that T1 be higher than T2. In this case, the heat shieldingproperties of laminated glass are enhanced. Because the heat shieldingproperties of laminated glass are further enhanced, it is preferred thatT1 be higher by 10% or more than T2, it is more preferred that T1 behigher by 15% or more than T2, it is more preferred that T1 be higher by20% or more than T2, it is still more preferred that T1 be higher by 30%or more than T2, it is further preferred that T1 be higher by 40% ormore than T2, it is still further preferred that T1 be higher by 50% ormore than T2 and it is especially preferred that T1 be higher by 60% ormore than T2. Although the upper limit of a value of (T1-T2) is notparticularly limited, because the transparency of laminated glass isfurther enhanced, it is preferred that (T1-T2) be less than or equal to90%, it is more preferred that (T1-T2) be less than or equal to 85% andit is further preferred that (T1-T2) be less than or equal to 80%.

In this connection, the infrared ray transmittance T1 in the wavelengthof 780 to 2100 nm of the whole layer composed of a first laminated glassmember and a first resin layer is measured in the following manner.

Laminated glass in which a first laminated glass member, a first resinlayer and a sheet of clear glass (2.5 mm in thickness) are layered inthis order is prepared. Weighting factors in the range of 780 to 2100 nmamong weighting factors in the range of 300 to 2100 nm shown in AppendixTable 2 in JIS R3106 (1998) are used, and each of weighting factors inthe range of 780 to 2100 nm is divided by the total value of weightingfactors in the range of 780 to 2100 nm to obtain a newly normalizedweighting factor of the infrared ray transmittance in the range of 780to 2100 nm. Then, the spectral transmittance in the wavelength of 780 to2100 nm of a sheet of laminated glass is obtained in accordance with JISR3106 (1998) using a spectrophotometer (“U-4100” available from HitachiHigh-Technologies Corporation). The spectral transmittance obtained ismultiplied by the newly normalized weighting factor to calculate theinfrared ray transmittance T1 in the wavelength of 780 to 2100 nm.

Moreover, the infrared ray transmittance T2 in the wavelength of 780 to2100 nm of the whole layer composed of a second laminated glass memberand a second resin layer is measured in the following manner.

Laminated glass in which a second laminated glass member, a second resinlayer and a sheet of clear glass (2.5 mm in thickness) are layered inthis order is prepared. Weighting factors in the range of 780 to 2100 nmamong weighting factors in the range of 300 to 2100 nm shown in AppendixTable 2 in JIS R3106 (1998) are used, and each of weighting factors inthe range of 780 to 2100 nm is divided by the total value of weightingfactors in the range of 780 to 2100 nm to obtain a newly normalizedweighting factor of the infrared ray transmittance in the range of 780to 2100 nm. Then, the spectral transmittance in the wavelength of 780 to2100 nm of a sheet of laminated glass is obtained in accordance with JISR3106 (1998) using a spectrophotometer (“U-4100” available from HitachiHigh-Technologies Corporation). The spectral transmittance obtained ismultiplied by the newly normalized weighting factor to calculate theinfrared ray transmittance T2 in the wavelength of 780 to 2100 nm.

Examples of the first and second laminated glass members include a glassplate and a PET (polyethylene terephthalate) film and the like. As thelaminated glass, laminated glass in which an interlayer film issandwiched between a glass plate and a PET film or the like, as well aslaminated glass in which an interlayer film is sandwiched between twoglass plates, is included. Laminated glass is a laminate provided with aglass plate, and it is preferred that at least one glass plate be used.It is preferred that each of the first and second laminated glassmembers be a glass plate or a PET (polyethylene terephthalate) film andthe interlayer film include at least one glass plate as the first orsecond laminated glass member. It is especially preferred that both ofthe first and second laminated glass members be glass plates.

Examples of the glass plate include a sheet of inorganic glass and asheet of organic glass. Examples of the inorganic glass include floatplate glass, heat ray-absorbing plate glass, heat ray-reflecting plateglass, polished plate glass, figured glass, net-reinforced plate glass,wired plate glass, green glass and the like. The organic glass issynthetic resin glass substituted for inorganic glass. Examples of theorganic glass include a polycarbonate plate, a poly(meth)acrylic resinplate, and the like. Examples of the poly(meth)acrylic resin plateinclude a polymethyl (meth)acrylate plate, and the like.

It is preferred that the first laminated glass member and the secondlaminated glass member be each a sheet of clear glass or a sheet of heatray-absorbing plate glass. Because the infrared ray transmittance isenhanced and the heat shielding properties of laminated glass arefurther enhanced, it is preferred that the first laminated glass memberbe a sheet of clear glass. Because the infrared ray transmittance islowered and the heat shielding properties of laminated glass are furtherenhanced, it is preferred that the second laminated glass member be asheet of heat ray-absorbing plate glass. It is preferred that the heatray-absorbing plate glass be green glass. It is preferred that the firstlaminated glass member be a sheet of clear glass and the secondlaminated glass member be a sheet of heat ray-absorbing plate glass. Theheat ray-absorbing plate glass is heat ray-absorbing plate glass inaccordance with SIS 83208.

Although the thickness of the first or second laminated glass member isnot particularly limited, the thickness is preferably greater than orequal to 1 mm and preferably less than or equal to 5 mm. In the casewhere the laminated glass member is a glass plate, the thickness of theglass plate is preferably greater than or equal to 1 mm and preferablyless than or equal to 5 mm. In the case where the laminated glass memberis a PET film, the thickness of the PET film is preferably greater thanor equal to 0.03 mm and preferably less than or equal to 0.5 mm.

The production method of the laminated glass is not particularlylimited. For example, the interlayer film mentioned above is sandwichedbetween the first and second laminated glass members, and the airremaining between the first or second laminated glass member and theinterlayer film is removed by allowing the members to pass through apressing roll or by putting the members into a rubber bag and allowingthe contents to be sucked under reduced pressure. Afterward, the membersare preliminarily bonded together at about 70 to 110° C. to obtain alaminate. Next, by putting the laminate into an autoclave or by pressingthe laminate, the members are press-bonded together at about 120 to 150°C. and under a pressure of 1 to 1.5 MPa. In this way, laminated glasscan be obtained.

The laminated glass can be used for automobiles, railway vehicles,aircraft, ships, buildings and the like. It is preferred that thelaminated glass be laminated glass for building or for vehicles, and itis more preferred that the laminated glass be laminated glass forvehicles. The interlayer film and the laminated glass can also be usedfor applications other than these applications. The interlayer film andthe laminated glass can be used for a windshield, side glass, rear glassor roof glass of an automobile and the like. Since the interlayer filmand the laminated glass are high in heat shielding properties and highin visible light transmittance, the interlayer film and the laminatedglass are suitably used for automobiles.

From the viewpoint of obtaining laminated glass further excellent intransparency, the visible light transmittance of laminated glass ispreferably higher than or equal to 60%, more preferably higher than orequal to 65% and further preferably higher than or equal to 70%. Thevisible light transmittance of laminated glass can be measured inaccordance with JIS R3211 (1998). The visible light transmittance oflaminated glass obtained by sandwiching the interlayer film forlaminated glass according to the present invention between two sheets ofgreen glass with a thickness of 2 mm in accordance with JIS R3208 ispreferably higher than or equal to 60%, more preferably higher than orequal to 65% and further preferably higher than or equal to 10%. Thevisible light transmittance of laminated glass obtained by sandwichingthe interlayer film for laminated glass according to the presentinvention between two sheets of clear glass with a thickness of 2 mm ispreferably higher than or equal to 60%, more preferably higher than orequal to 65% and further preferably higher than or equal to 70%.

From the viewpoint of obtaining laminated glass further excellent inheat shielding properties, the Tts of laminated glass obtained bysandwiching the interlayer film for laminated glass according to thepresent invention between two sheets of green glass with a thickness of2 mm in accordance with JIS R3208 is preferably lower than or equal to60%, more preferably lower than or equal to 55%, further preferablylower than or equal to 53%, especially preferably lower than or equal to51% and most preferably lower than or equal to 50%. From the viewpointof obtaining laminated glass further excellent in heat shieldingproperties, the Tts of laminated glass obtained by sandwiching theinterlayer film for laminated glass according to the present inventionbetween two sheets of clear glass with a thickness of 2 mm is preferablylower than or equal to 60%, more preferably lower than or equal to 55%,further preferably lower than or equal to 53%, especially preferablylower than or equal to 51% and most preferably lower than or equal to50%. The Tts is measured in accordance with ISO 13837.

From the viewpoint of obtaining laminated glass further excellent inheat shielding properties, the Tds of laminated glass obtained bysandwiching the interlayer film for laminated glass according to thepresent invention between two sheets of green glass with a thickness of2 mm in accordance with JIS R3208 is preferably lower than or equal to50%, more preferably lower than or equal to 45%, further preferablylower than or equal to 43% and especially preferably lower than or equalto 41%. From the viewpoint of obtaining laminated glass furtherexcellent in heat shielding properties, the Tds of laminated glassobtained by sandwiching the interlayer film for laminated glassaccording to the present invention between two sheets of clear glasswith a thickness of 2 mm is preferably lower than or equal to 50%, morepreferably lower than or equal to 45%, further preferably lower than orequal to 43% and especially preferably lower than or equal to 41%. TheTds is measured in accordance with ISO 13837.

The infrared ray transmittance (Tir) is determined by measuring a valueof infrared ray transmittance and normalizing the value with weightingfactors described in JIS Z8722 and JIS R3106.

Specifically, the infrared ray transmittance in the wavelength of 780 to2100 nm of a first resin layer, a second resin layer or the like ismeasured in the following manner.

A first resin layer or a second resin layer (an object to be measuredfor the infrared ray transmittance) and the like are interposed betweentwo sheets of clear glass (2.5 mm or 2 mm in thickness) to preparelaminated glass. Weighting factors in the range of 780 to 2100 nm amongweighting factors in the range of 300 to 2100 nm shown in Appendix Table2 in JIS R3106 (1998) are used, and each of weighting factors in therange of 780 to 2100 nm is divided by the total value of weightingfactors in the range of 780 to 2100 nm to obtain a newly normalizedweighting factor of the infrared ray transmittance in the range of 780to 2100 nm. Then, the spectral transmittance in the wavelength of 780 to2100 nm of a sheet of laminated glass is obtained in accordance with JISR3106 (1998) using a spectrophotometer (“U-4100” available from HitachiHigh-Technologies Corporation). The spectral transmittance obtained ismultiplied by the newly normalized weighting factor to calculate theinfrared ray transmittance in the wavelength of 780 to 2100 nm.

The haze value of laminated glass is preferably lower than or equal to2%, more preferably lower than or equal to 1%, further preferably lowerthan or equal to 0.5% and especially preferably lower than or equal to0.4%. The haze value of laminated glass can be measured in accordancewith JIS K6714.

(Method for Fitting Laminated Glass)

The method for fitting laminated glass according to the presentinvention is a method for fitting the above-described laminated glassfor a building or a vehicle into an opening part between an outer spaceand an inner space into which heat rays are made incident from the outerspace.

Specifically, the laminated glass is fitted into an opening part so thatthe first laminated glass member is positioned at the outer space sideand the second laminated glass member is positioned at the inner spaceside. That is, the laminated glass is fitted so that an arrangementorder of the outer space/a first laminated glass member/(anotherlayer/)a first resin layer/(another layer/)an infrared ray reflectionlayer/(another layer/)a second resin layer/(another layer/)a secondlaminated glass member/the inner space is attained. Preferably, it ispreferred that an arrangement order of the outer space/a first laminatedglass member/a first resin layer/(another layer/)an infrared rayreflection layer/(another layer/) a second resin layer/a secondlaminated glass member/the inner space be attained, it is preferred thatan arrangement order of the outer space/a first laminated glassmember/(another layer/)a first resin layer/an infrared ray reflectionlayer/a second resin layer/(another layer/)a second laminated glassmember/the inner space be attained, and it is preferred that anarrangement order of the outer space/a first laminated glass member/afirst resin layer/an infrared ray reflection layer/a second resinlayer/a second laminated glass member/the inner space be attained. Inthe above-mentioned arrangement forms, the case where another member isarranged between the outer space and the first laminated glass member isincluded, and the case where another member is arranged between theinner space and the second laminated glass member is included.

In the layered structure, each of another layer mentioned above andanother member mentioned above may be present or may be absent. Sunlightcontaining heat rays is made incident into laminated glass from an outerspace, and the sunlight containing heat rays, which has passed throughthe laminated glass, is led to an inner space. In the case wherelaminated glass is fitted into an opening part as mentioned above, theouter surface of the first laminated glass member constitutes theincident face for heat rays. Moreover, heat rays are made incident intothe first resin layer earlier than the second resin layer.

Hereinafter, the present invention will be described in more detail withreference to examples. The present invention is not limited only to thefollowing examples.

The following materials were used to form first and second resin layers.

Thermoplastic Resin:

Polyvinyl butyral resins PVB1 to PVB7 (any of these is a polyvinylbutyral resin (PVB) acetalized with n-butyraldehyde) shown in thefollowing Table 1 were prepared.

TABLE 1 Content ratio of Kind of Average hydroxyl AcetylationButyralization thermoplastic polymerization group degree degree resindegree (mol %) (mol %) (mol %) PVB1 1700 30.5 1 68.5 PVB2 1700 19 20 61PVB3 1700 16.5 0.5 83 PVB4 1700 38.5 1 60.5 PVB5 3000 22 13 65 PVB6 300019 20 61 PVB7 3000 16.5 0.5 83

Plasticizer:

3GO (triethylene glycol di-2-ethylhexanoate)

Other Ingredients:

T-326 (an ultraviolet ray shielding agent,2-(2′-hydroxy-3′-t-butyl-5-methylphenyl)-5-chlorobenzotriazole, “Tinuvin326” available from BASF Japan Ltd.)

BHT (an oxidation inhibitor, 2,6-di-t-butyl-p-cresol)

ITO (ITO particles, tin-doped indium oxide particles)

CWO (CWO particles, cesium-doped tungsten oxide (Cs_(0.33)WO₃)particles)

43V (Ingredient X, a phthalocyanine compound, “NIR-43V” available fromYAMADA CHEMICAL CO., LTD. which contains a vanadium atom as the centralmetal)

A metal salt (an adhesive force regulating agent, magnesium acetatetetrahydrate)

Moreover, the following infrared ray reflection layers were prepared.

XIR-75 (a resin film with metal foil, “XIR-75” available from SouthwallTechnologies Inc.)

A multilayer film (3M, a multilayer resin film, “Multilayer Nano 80S”available from 3M Japan Limited)

Moreover, the following laminated glass members (sheets of glass) wereprepared.

Clear glass (300 cm in longitudinal length by 300 cm in transversallength by 2 mm in thickness)

Green glass (heat ray-absorbing plate glass in accordance with JISR3208, 300 cm in longitudinal length by 300 cm in transversal length by2 mm in thickness)

Light green glass (heat ray-absorbing plate glass in accordance with JISR3208, 300 cm in longitudinal length by 300 cm in transversal length by2 mm in thickness)

Dark green glass (heat ray-absorbing plate glass in accordance with JISR3208, 300 cm in longitudinal length by 300 cm in transversal length by2 mm in thickness)

UV green glass (heat ray-absorbing plate glass in accordance with JISR3208, 300 cm in longitudinal length by 300 cm in transversal length by2 mm in thickness)

(Preparation of Resin Layer A1)

To 100 parts by weight of a polyvinyl butyral resin (PVB1), 40 parts byweight of a plasticizer (3GO), 0.8 part by weight of an ultraviolet rayshielding agent (T-326), 0.2 part by weight of an oxidation inhibitor(BHT) and magnesium acetate tetrahydrate in an amount that the metalelement concentration becomes 45.6 ppm in the resulting resin layer A1were added and thoroughly kneaded with a mixing roll to obtain acomposition.

The composition obtained was extruded by an extruder to obtain asingle-layered resin layer A1 with a thickness of 380 μm.

(Preparation of Resin Layers A2 to A7)

Single-layered resin layers A2 to A7 with a thickness of 380 μm wereobtained in the same manner as that for the resin layer A1 except thatthe kind of ingredients to be blended and the blending amount thereofwere set to those listed in the following Table 2.

(Preparation of Resin Layer A8)

To 100 parts by weight of a polyvinyl butyral resin (PVB1), 40 parts byweight of a plasticizer (3GO), 0.2 part by weight of an ultraviolet rayshielding agent (T-326), 0.2 part by weight of an oxidation inhibitor(BHT) and magnesium acetate tetrahydrate in an amount that the metalelement concentration becomes 45.6 ppm in the resulting resin layer A8were added and thoroughly kneaded with a mixing roll to obtain acomposition.

The composition obtained was extruded by an extruder to obtain a resinlayer A8 having a dividedly dyed part (a shaded part) with a thicknessof 760 μm.

(Preparation of Resin Layer A9)

To 100 parts by weight of a polyvinyl butyral resin (PVB1), 40 parts byweight of a plasticizer (3GO), 0.2 part by weight of an ultraviolet rayshielding agent (T-326), 0.2 part by weight of an oxidation inhibitor(BHT) and magnesium acetate tetrahydrate in an amount that the metalelement concentration becomes 45.6 ppm in the resulting resin layer A9were added and thoroughly kneaded with a mixing roll to obtain acomposition.

The composition obtained was extruded by an extruder to obtain a resinlayer A9 having a wedge shape.

TABLE 2 Composition of first resin layer PVB 3GO T-326 BHT Kind of Partsby Parts by Parts by Parts by Metal salt first resin layer Kind weightweight weight weight ppm A1 PVB1 100 40 0.8 0.2 45.6 A2 PVB1 100 36 0.20.2 45.6 A3 PVB1 100 36 0.8 0.2 45.6 A4 PVB1 100 40 0.2 0.2 45.6 A5 PVB2100 36 0.8 0.2 45.6 A6 PVB3 100 36 0.8 0.2 45.6 A7 PVB4 100 36 0.8 0.245.6 A8 PVB1 100 40 0.2 0.2 45,6 A9 PVB1 100 40 0.2 0.2 45.6

(Preparation of Resin Layer A10)

To 100 parts by weight of a polyvinyl butyral resin (PVB1), 40 parts byweight of a plasticizer (3GO) and magnesium acetate tetrahydrate in anamount that the metal element concentration becomes 45.6 ppm in theresulting surface layer (an amount that the metal element concentrationbecomes 36.48 ppm in the resulting resin layer A10) were added andthoroughly kneaded with a mixing roll to obtain a composition for thesurface layer. To 100 parts by weight of a polyvinyl butyral resin(PVB5), 60 parts by weight of a plasticizer (3GO) was added andthoroughly kneaded with a mixing roll to obtain a composition for thecore layer. The composition for the surface layer and the compositionfor the core layer were coextruded by an extruder to obtain amulti-layered resin layer A10 with a thickness of 500 μm. The resinlayer A10 obtained has a layered structure with a stack of a surfacelayer (200 μm in thickness)/a core layer (100 μm in thickness)/a surfacelayer (200 μm in thickness).

(Preparation of Resin Layers A11 to A14)

Three-layered resin layers A11 to A14 with a thickness of 500 μm wereprepared in the same manner as that for the resin layer A10 except thatthe kind of ingredients to be blended and the content thereof were setto those listed in the following Table 3

TABLE 3 Composition of first resin layer Surface layer Core layer PVB3GO T-326 BHT PVB 3GO T-326 BHT Kind of Parts by Parts by Parts by Partsby Metal salt Parts by Parts by Parts by Parts by first resin layer Kindweight weight weight weight ppm Kind weight weight weight weight A10PVB1 100 40 — — 45.6 PVB5 100 60 — — A11 PVB2 100 40 — — 45.6 PVB5 10060 — — A12 PVB3 100 40 — — 45.6 PVB5 100 60 — — A13 PVB1 100 40 — — 45.6PVB6 100 60 — — A14 PVB1 100 40 — — 45.6 PVB7 100 60 — —

(Preparation of Resin Layers A15 to A17)

Single-layered resin layers A15 to A17 with a thickness of 380 μm wereobtained in the same manner as that for the resin layer A1 except thatthe kind of ingredients to be blended and the blending amount thereofwere set to those listed in the following Table 4.

TABLE 4 Composition of first resin layer PVB 3GO T-326 BHT Kind of Partsby Parts by Parts by Parts by Metal salt first resin layer Kind weightweight weight weight ppm A15 PVB1 100 36 0.2 0.2 25.6 A16 PVB1 100 360.2 0.2 65.6 A17 PVB1 100 36 0.2 0.2 —

(Preparation of Resin Layers A18 to A20)

Three-layered resin layers A18 to A20 with a thickness of 500 μm wereprepared in the same manner as that for the resin layer A10 except thatthe kind of ingredients to be blended and the content thereof were setto those listed in the following Table 5.

TABLE 5 Composition of first resin layer Surface layer Core layer PVB3GO T-326 BHT PVB 3GO T-326 BHT Kind of Parts by Parts by Parts by Partsby Metal salt Parts by Parts by Parts by Parts by first resin layer Kindweight weight weight weight ppm Kind weight weight weight weight A18PVB1 100 40 — — 25.6 PVB5 100 60 — — A19 PVB1 100 40 — — 65.6 PVB5 10060 — — A20 PVB1 100 40 — — — PVB5 100 60 — —

(Preparation of Resin Layer B1)

To 40 parts by weight of a plasticizer (3GO), heat shielding particles(ITO) in an amount that the content thereof in the resulting resin layerB1 becomes 0.4% by weight and an Ingredient X (43V) in an amount thatthe content thereof in the resulting resin layer B1 becomes 0.008% byweight were added and mixed to obtain a plasticizer dispersion.

To 100 parts by weight of a polyvinyl butyral resin (PVB1) the wholeamount of the plasticizer dispersion, 0.8 part by weight of anultraviolet ray shielding agent (T-326), 0.2 part by weight of anoxidation inhibitor (BHT) and magnesium acetate tetrahydrate in anamount that the metal element concentration becomes 94.3 ppm in theresulting resin layer B1 were added and thoroughly kneaded with a mixingroll to obtain a composition.

The composition obtained was extruded by an extruder to obtain asingle-layered resin layer B1 with a thickness of 380 μm.

(Preparation of Resin Layers B2 to B21)

Single-layered resin layers B2 to B21 with a thickness of 380 μm wereprepared in the same manner as that for the resin layer B1 except thatthe kind of ingredients to be blended and the content thereof were setto those listed in the following Table 6.

In this connection, in the foregoing Tables 2 to 5 and the followingTable 6, the amounts of 3GO, T-326 and BHT blended refer to the blendingamounts thereof (parts by weight) relative to 100 parts by weight of thepolyvinyl butyral resin (PVB). The amounts of ITO, CWO and 43V blendedrefer to the blending amounts thereof (% by weight) in 100% by weight ofthe resin layer. The amount of a metal salt blended refers to the metalelement (Mg) concentration in the resin layer. Moreover, with regard toeach of the alkali metal, the alkaline earth metal and Mg, the totalcontent thereof in the first and second resin layers was determined tobe less than or equal to 150 ppm.

TABLE 6 Composition of second resin layer Kind of second PVB1 3GO T-326BHT ITO CWO 43V Metal salt resin layer Parts by weight Parts by weightParts by weight Parts by weight % by weight % by weight % by weight ppmB1 100 40 0.8 0.2 0.4 — 0.008 94.3 B2 100 40 0.8 0.2 0.2 — — 94.3 B3 10040 0.8 0.2 0.8 0.1 0.006 94.3 B4 100 40 0.8 0.2 0.8 — 0.012 94.3 B5 10040 0.8 0.2 0.28 0.048 0.012 94.3 B6 100 36 0.8 0.4 0.8 — 0.009 94.3 B7100 36 0.8 0.4 1.17 — 0.009 94.3 B8 100 36 0.8 0.4 0.7 — 0.007 94.3 B9100 36 0.8 0.4 1.32 — 0.014 94.3 B10 100 36 0.8 0.4 1.67 — 0.018 94.3B11 100 36 0.8 0.4 0.8 — 0.009 74.3 B12 100 36 0.8 0.4 0.8 — 0.009 114.3B13 100 36 0.8 0.4 0.8 — 0.009 — B14 100 36 0.8 0.2 0.833 — 0.009 94.3B15 100 36 0.8 0.2 0.66 0.01 0.009 94.3 B16 100 36 0.8 0.2 0.51 0.020.009 94.3 B17 100 36 0.8 0.2 0.28 0.04 0.009 94.3 B18 100 36 0.8 0.20.72 — 0.01 94.3 B19 100 36 0.8 0.2 0.22 0.04 0.01 94.3 B20 100 36 0.80.2 0.64 — 0.011 94.3 B21 100 36 0.8 0.2 0.2 0.04 0.011 94.3

Example 1

(1) Preparation of Interlayer Film for Laminated Glass

As an infrared ray reflection layer, XIR-75 (a resin film with metalfoil, “XIR-75” available from Southwall Technologies Inc.) was prepared.

The XIR-75 prepared was used as an infrared ray reflection layer and theinfrared ray reflection layer was sandwiched between a resin layer A1obtained and a resin layer B1 obtained to obtain an interlayer film.

(2) Preparation of Laminated Glass

The interlayer film obtained was cut into a size of 30 cm inlongitudinal length by 30 cm in transversal length. Moreover, two sheetsof clear glass (30 cm in longitudinal length by 30 cm in transversallength by 2.5 mm in thickness) were prepared. The interlayer filmobtained was sandwiched between the two sheets of clear glass, held inplace for 30 minutes at 90° C. and pressed under vacuum with a vacuumlaminator to obtain a laminate. With regard to the laminate, interlayerfilm portions protruded from the glass plate were cut away to obtain asheet of laminated glass.

Examples 2 to 47

Interlayer films and sheets of laminated glass were prepared in the samemanner as that in Example 1 except that the kind of first and secondresin layers, the kind of an infrared ray reflection layer and the kindof first and second laminated glass members were set to those listed inthe following Table 7.

Comparative Example 1

Without using an infrared ray reflection layer, a resin layer A1obtained and a resin layer B5 obtained were layered to obtain aninterlayer film. A sheet of laminated glass was obtained in the samemanner as that in Example 1 except that the interlayer film obtained wasused and the first and second laminated glass members were changed tosheets of green glass.

Comparative Example 2

The same infrared ray reflection layer as that in Example 1 wassandwiched between a resin layer A1 obtained and a resin layer A1obtained to obtain an interlayer film. A sheet of laminated glass wasobtained in the same manner as that in Example 1 except that theinterlayer film obtained was used.

Comparative Example 3

As an infrared ray reflection layer, a multilayer film (3M, a multilayerresin film, “Multilayer Nano 80S” available from 3M Japan Limited) wasprepared.

The multilayer film prepared was used alone as an infrared rayreflection layer and the infrared ray reflection layer was sandwichedbetween a resin layer A1 obtained and a resin layer A1 obtained toobtain an interlayer film. A sheet of laminated glass was obtained inthe same manner as that in Example 1 except that the interlayer filmobtained was used.

Comparative Example 4

As an infrared ray reflection layer, a multilayer film (3M, a multilayerresin film, “Multilayer Nano 80S” available from 3M Japan Limited) wasprepared.

The multilayer film prepared was used alone as an infrared rayreflection layer and the infrared ray reflection layer was sandwichedbetween a resin layer A1 obtained and a resin layer A1 obtained toobtain an interlayer film. A sheet of laminated glass was obtained inthe same manner as that in Example 1 except that the interlayer filmobtained was used and the first and second laminated glass members werechanged to sheets of green glass.

Comparative Example 5

Without using an infrared ray reflection layer, a resin layer A1obtained and a resin layer B1 obtained were layered to obtain aninterlayer film. A sheet of laminated glass was obtained in the samemanner as that in Example 1 except that the interlayer film obtained wasused.

(Evaluation)

(1) Measurement of Visible Light Transmittance (A Light Y Value, A-Y(380 to 780 nm))

The laminated glass obtained was measured for the visible lighttransmittance in the wavelength of 380 to 780 nm in accordance with JISR3211 (1998) using a spectrophotometer (“U-4100” available from HitachiHigh-Technologies Corporation).

(2) Measurement of Tds (Direct Solar Energy Transmitted Through aGlazing)

The laminated glass obtained was measured for the Tds in the wavelengthof 300 to 2500 nm in accordance with ISO 13837 using a spectrophotometer(“U-4100” available from Hitachi High-Technologies Corporation).

(3) Measurement of Tds (Total Solar Energy Transmitted Through aGlazing)

The transmittance/reflectance in the wavelength of 300 to 2500 nm wasmeasured using a spectrophotometer (“U-4100” available from HitachiHigh-Technologies Corporation) in accordance with ISO 13837 to calculatethe Tts.

(4) Penetration Resistance

The penetration resistance was judged according to the followingcriteria.

The surface temperature of the sheet of laminated glass (30 cm inlongitudinal length by 30 cm in transversal length) obtained wasadjusted to 23° C. Then, in accordance with JIS R3212, a hard spherewith a mass of 2260 g and a diameter of 82 mm was dropped at the centerpart of each of six sheets of laminated glass from a height of 5 m. Inthe case where the hard sphere does not penetrate through each of allthe six sheets of laminated glass within 5 seconds after the hard spherehas collided therewith, the laminated glass is acceptable (Circle). Inthe case where sheets of laminated glass through each of which the hardsphere does not penetrate within 5 seconds after the hard sphere hascollided therewith are three or less sheets, the laminated glass is notacceptable (X mark). In the case where sheets of laminated glass througheach of which the hard sphere does not penetrate are four sheets,separately, six sheets of laminated glass are evaluated for thepenetration resistance. In the case where sheets of laminated glassthrough each of which the hard sphere does not penetrate are fivesheets, separately, one sheet of laminated glass is additionally tested.In the case where the hard sphere does not penetrate through the sheetof laminated glass within 5 seconds after the hard sphere has collidedtherewith, the laminated glass is acceptable. In the same manner, a hardsphere with a mass of 2260 g and a diameter of 82 mm was dropped at thecenter part of each of six sheets of laminated glass from a height of 5m, 6 m or 7 m to evaluate the penetration resistance of laminated glass.In this connection, with regard to Examples 36 to 39 in which a resinlayer containing no metal salt is used, as compared with other examples,there is a tendency that the size of glass fragments becomes large. Inthis connection, in all of the examples and comparative examples,respective sheets of laminated glass were determined to be acceptable(Circle) even in the case where the height from which the hard sphere isdropped was 5 m, 6 m or 7 m.

The layered configuration of laminated glass and evaluation results areshown in the following Tables 7 and 8. When the infrared raytransmittance in the wavelength of 780 to 2100 nm of the first resinlayer is defined as Tx1 and the infrared ray transmittance in thewavelength of 780 to 2100 nm of the second resin layer is defined asTx2, the relationship between Tx1 and Tx2 is described in the column of“Resin layer” of the infrared ray transmittance of the following Table8. When the infrared ray transmittance in the wavelength of 780 to 2100nm of the first laminated glass member is defined as Ty1 and theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond laminated glass member is defined as Ty2, the relationshipbetween Ty1 and Ty2 is described in the column of “Laminated glassmember” of the infrared ray transmittance of the following Table 8.

In this connection, the infrared ray transmittance Tx1 or Tx2 in thewavelength of 780 to 2100 nm of a first resin layer or a second resinlayer was measured in the following manner. A first resin layer or asecond resin layer was interposed between two sheets of clear glass (2.5mm in thickness) to prepare laminated glass. Weighting factors in therange of 780 to 2100 nm shown in Appendix Table 2 in JIS R3106 (1998)were used and normalized as new weighting factors for the infrared raytransmittance. Then, the spectral transmittance in the wavelength of 780to 2100 nm of a sheet of laminated glass was obtained in accordance withJIS R3106 (1998) using a spectrophotometer (“U-4100” available fromHitachi High-Technologies Corporation). The spectral transmittanceobtained was multiplied by the newly normalized weighting factor tocalculate the infrared ray transmittance in the wavelength of 780 to2100 nm. That is, weighting factors in the range of 780 to 2100 nm amongweighting factors in the range of 300 to 2100 nm shown in Appendix Table2 in JIS R3106 (1998) were used, and each of weighting factors in therange of 780 to 2100 nm was divided by the total value of weightingfactors in the range of 780 to 2100 nm to obtain a newly normalizedweighting factor of the infrared ray transmittance in the range of 780to 2100 nm. Then, the spectral transmittance in the wavelength of 780 to2100 nm of a sheet of laminated glass was obtained in accordance withJIS R3106 (1998) using a spectrophotometer (“U-4100” available fromHitachi High-Technologies Corporation). The spectral transmittanceobtained was multiplied by the newly normalized weighting factor tocalculate the infrared ray transmittance Tx1 or Tx2 in the wavelength of780 to 2100 nm. Similarly, a first laminated glass member or a secondlaminated glass member as a glass plate-made single plate was measuredfor the infrared ray transmittance Ty1 or Ty2 in the wavelength of 780to 2100 nm.

Moreover, in Example 18 where a resin layer A9 having a wedge shape isused, a portion with a thickness of 760 μm of the resin layer A9 havinga wedge shape was measured for the Tx1, A-Y, Tds and Tts.

TABLE 7 Layered configuration Infrared First ray Second Evaluation Firstlaminated resin reflection resin Second laminated A-Y Tds TtsPenetration glass member layer layer layer glass member (%) (%) (%)resistance Ex. 1 Clear A1  XIR-75 B1  Clear 72.6 41.0 50.4 ○ Ex. 2 ClearA1  XIR-75 B2  Green 70.0 24.8 49,6 ○ Ex. 3 Clear A1  3M B3  Clear 76.639.2 50.4 ○ Ex. 4 Clear A1  3M B4  Green 76.1 38.6 49.9 ○ Ex. 5 GreenA1  3M B3  Green 71.5 35.9 50.3 ○ Ex. 6 Clear A1  3M B6  Green 75.9 37.649.1 ○ Ex. 7 Clear A2  3M B6  Green 77.1 38.0 49.0 ○ Ex. 8 Clear A3  3MB6  Green 77.7 40.0 50.5 ○ Ex. 9 Clear A4  3M B6  Green 77.8 40.2 50.8 ○Ex. 10 Clear A5  3M B6  Green 77.9 40.3 50.7 ○ Ex. 11 Clear A6  3M B6 Green 77.8 40.2 50.8 ○ Ex. 12 Clear A7  3M B6  Green 77.7 39.7 50.5 ○Ex. 13 Clear A2  3M B7  Green 75.4 36.7 48.2 ○ Ex. 14 Clear A2  3M B8 Green 79.2 41.0 51.7 ○ Ex. 15 Clear A2  3M B9  Green 76.7 37.7 49.2 ○Ex. 16 Clear A2  3M B10 Green 73.7 34.2 46.6 ○ Ex. 17 Clear A8  3M B6 Green 77.7 40.0 50.7 ○ Ex. 18 Clear A9  3M B6  Green 77.8 38.4 49.5 ○Ex. 19 Clear A10 3M B6  Green 78.1 39.0 50.1 ○ Ex. 20 Clear A11 3M B6 Green 77.8 40.2 51.0 ○ Ex. 21 Clear A12 3M B6  Green 77.9 40.3 51.0 ○Ex. 22 Clear A13 3M B6  Green 77.8 40.2 50.9 ○ Ex. 23 Clear A14 3M B6 Green 78.1 39.5 50.3 ○ Ex. 24 Clear A3  3M B6  Light green 77.5 39.0 521○ Ex. 25 Clear A3  3M B6  Dark green 72.8 34.6 49.1 ○ Ex. 26 Clear A3 3M B6  UV green 74.7 36.6 47.8 ○ Ex. 27 Light green A3  3M B6  Lightgreen 73.5 34.7 49.1 ○ Ex. 28 Clear A15 3M B6  Green 77.1 38.0 49.0 ○Ex. 29 Clear A16 3M B6  Green 77.1 38,0 49.0 ○ Ex. 30 Clear A18 3M B6 Green 78.1 39.0 50.1 ○ Ex. 31 Clear A19 3M B6  Green 78.1 39.0 50.1 ○Ex. 32 Clear A1  3M B11 Green 77.1 38.0 49.0 ○ Ex. 33 Clear A1  3M B12Green 77.1 38.0 49.0 ○ Ex. 34 Clear A10 3M B11 Green 78.1 39.0 50.1 ○Ex. 35 Clear A10 3M B12 Green 78.1 39.0 50.1 ○ Ex. 36 Clear A17 3M B6 Green 77.1 38.0 49.0 ○ Ex. 37 Clear A20 3M B6  Green 78.1 39.0 50.1 ○Ex. 38 Clear A1  3M B13 Green 77.1 38.0 49.0 ○ Ex. 39 Clear A10 3M B13Green 78.1 39.0 50.1 ○ Ex. 40 Clear A2  3M B14 Green 76.9 39.1 50.3 ○Ex. 41 Clear A2  3M B15 Green 76.8 39.2 50.3 ○ Ex. 42 Clear A2  3M B16Green 76.6 39.1 50.3 ○ Ex. 43 Clear A2  3M B17 Green 76.2 39.1 50.3 ○Ex. 44 Clear A2  3M B18 Green 77.0 39.2 50.3 ○ Ex. 45 Clear A2  3M B19Green 76.1 39.2 50.4 ○ Ex. 46 Clear A2  3M B20 Green 76.9 39.1 50.3 ○Ex. 47 Clear A2  3M B21 Green 75.9 39.0 50.2 ○ Comp. Ex. 1 Green A1  —B5  Green 74.9 41.4 56.1 ○ Comp. Ex. 2 Clear A1  XIR-75 A1  Clear 75.647.5 55.1 ○ Comp. Ex. 3 Clear A1  3M A1  Clear 83.1 54.5 61.6 ○ Comp.Ex. 4 Green A1  3M A1  Green 78.6 45.7 57.0 ○ Comp. Ex. 5 Clear A1  —B1  Clear 85.2 60.9 69.7 ○

TABLE 8 Resin layer Laminated glass member Tx1 Tx2 Ty1 Ty2 (%) (%) Tx1 −Tx2 (%) (%) Ty1 − Ty2 Ex. 1 Tx1 > Tx2 76.1 49.8 26.3 Ty1 = Ty2 85.3 85.30.0 Ex. 2 Tx1 > Tx2 76.1 57.1 19 Ty1 > Ty2 85.3 61.1 24.2 Ex. 3 Tx1 >Tx2 76.1 27.7 48.4 Ty1 = Ty2 85.3 85.3 0.0 Ex. 4 Tx1 > Tx2 76.1 39.336.8 Ty1 > Ty2 85.3 61.1 24.2 Ex. 5 Tx1 > Tx2 76.1 27.7 48.4 Ty1 = Ty261.1 61.1 0.0 Ex. 6 Tx1 > Tx2 76.1 40.3 35.8 Ty1 > Ty2 85.3 61.1 24.2Ex. 7 Tx1 > Tx2 76.3 40.3 36 Ty1 > Ty2 85.3 61.1 24.2 Ex. 8 Tx1 > Tx275.9 40.3 35.6 Ty1 > Ty2 85.3 61.1 24.2 Ex. 9 Tx1 > Tx2 76.2 40.3 35.9Ty1 > Ty2 85.3 61.1 24.2 Ex. 10 Tx1 > Tx2 75.9 40.3 35.6 Ty1 > Ty2 85.361.1 24.2 Ex. 11 Tx1 > Tx2 75.9 40.3 35.6 Ty1 > Ty2 85.3 61.1 24.2 Ex.12 Tx1 > Tx2 75.9 40.3 35.6 Ty1 > Ty2 85.3 61.1 24.2 Ex. 13 Tx1 > Tx276.3 38.3 38 Ty1 > Ty2 85.3 61.1 24.2 Ex. 14 Tx1 > Tx2 76.3 41.3 35Ty1 > Ty2 85.3 61.1 24.2 Ex. 15 Tx1 > Tx2 76.3 37.3 39 Ty1 > Ty2 85.361.1 24.2 Ex. 16 Tx1 > Tx2 76.3 36.3 40 Ty1 > Ty2 85.3 61.1 24.2 Ex. 17Tx1 > Tx2 76.2 40.3 35.9 Ty1 > Ty2 85.3 61.1 24.2 Ex. 18 Tx1 > Tx2 76.240.3 35.9 Ty1 > Ty2 85.3 61.1 24.2 Ex. 19 Tx1 > Tx2 75.8 40.3 35.5 Ty1 >Ty2 85.3 61.1 24.2 Ex. 20 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.124.2 Ex. 21 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex. 22Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex. 23 Tx1 > Tx2 75.840.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex. 24 Tx1 > Tx2 75.9 40.3 35.6 Ty1 >Ty2 85.3 57.5 27.8 Ex. 25 Tx1 > Tx2 75.9 40.3 35.6 Ty1 > Ty2 85.3 55.529.8 Ex. 26 Tx1 > Tx2 75.9 40.3 35.6 Ty1 > Ty2 85.3 56.0 29.3 Ex. 27Tx1 > Tx2 75.9 40.3 35.6 Ty1 = Ty2 57.5 57.5 0.0 Ex. 28 Tx1 > Tx2 76.340.3 36 Ty1 > Ty2 85.3 61.1 24.2 Ex. 29 Tx1 > Tx2 76.3 40.3 36 Ty1 > Ty285.3 61.1 24.2 Ex. 30 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2Ex. 31 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex. 32 Tx1 >Tx2 76.3 40.3 36 Ty1 > Ty2 85.3 61.1 24.2 Ex. 33 Tx1 > Tx2 76.3 40.3 36Ty1 > Ty2 85.3 611 24.2 Ex. 34 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.361.1 24.2 Ex. 35 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex.36 Tx1 > Tx2 76.3 40.3 36.0 Ty1 > Ty2 85.3 61.1 24.2 Ex. 37 Tx1 > Tx275.8 40.3 35.5 Ty1 > Ty2 85.3 61.1 24.2 Ex. 38 Tx1 > Tx2 76.3 40.3 36.0Ty1 > Ty2 85.3 61.1 24.2 Ex. 39 Tx1 > Tx2 75.8 40.3 35.5 Ty1 > Ty2 85.361.1 24.2 Ex. 40 Tx1 > Tx2 76.3 42.0 34.3 Ty1 > Ty2 85.3 61.1 24.2 Ex.41 Tx1 > Tx2 76.3 42.2 34.1 Ty1 > Ty2 85.3 61.1 24.2 Ex. 42 Tx1 > Tx276.3 42.1 34.2 Ty1 > Ty2 85.3 61.1 24.2 Ex. 43 Tx1 > Tx2 76.3 42.1 34.2Ty1 > Ty2 85.3 61.1 24.2 Ex. 44 Tx1 > Tx2 76.3 43.9 32.4 Ty1 > Ty2 85.361.1 24.2 Ex. 45 Tx1 > Tx2 76.3 44.0 32.3 Ty1 > Ty2 85.3 61.1 24.2 Ex.46 Tx1 > Tx2 76.3 45.5 30.8 Ty1 > Ty2 85.3 61.1 24.2 Ex. 47 Tx1 > Tx276.3 44.7 31.6 Ty1 > Ty2 85.3 61.1 24.2 Comp. Ex.1 Tx1 > Tx2 76.1 40.835.3 Ty1 = Ty2 61.1 61.1 0.0 Comp. Ex.2 Tx1 = Tx2 76.1 76.1 0.0 Ty1 =Ty2 85.3 85.3 0.0 Comp. Ex.3 Tx1 = Tx2 76.1 76.1 0.0 Ty1 = Ty2 85.3 85.30.0 Comp. Ex.4 Tx1 = Tx2 76.1 76.1 0.0 Ty1 = Ty2 61.1 61.1 0.0 Comp.Ex.5 Tx1 > Tx2 76.1 49.8 26.3 Ty1 = Ty2 85.3 85.3 0.0

EXPLANATION OF SYMBOLS

-   -   1: Interlayer film    -   1 a: First surface    -   1 b: Second surface    -   2: Infrared ray reflection layer    -   2 a: First surface    -   2 b: Second surface    -   3: First resin layer    -   3 a: Outer surface    -   4: Second resin layer    -   4 a: Outer surface    -   11: Laminated glass    -   21: First laminated glass member    -   22: Second laminated glass member

1-12. (canceled)
 13. A laminated glass, comprising a first laminatedglass member, a second laminated glass member and an interlayer filmarranged between the first laminated glass member and the secondlaminated glass member; and the first laminated glass member and thesecond laminated glass member each being a clear glass other than a heatray-absorbing plate glass, or the first laminated glass member and thesecond laminated glass member each being a heat ray-absorbing plateglass, the interlayer film including an infrared ray reflection layerwhich reflects infrared rays, a first resin layer which is arranged on afirst surface side of the infrared ray reflection layer and contains athermoplastic resin, and a second resin layer which is arranged on asecond surface side opposite to the first surface of the infrared rayreflection layer and contains a thermoplastic resin, the first laminatedglass member being arranged on the outside of the first resin layer inthe interlayer film, and the second laminated glass member beingarranged on the outside of the second resin layer in the interlayerfilm, and the infrared ray transmittance in the wavelength of 780 to2100 nm of the first resin layer being higher by 10% or more than theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond resin layer.
 14. The laminated glass according to claim 13,wherein the infrared ray transmittance in the wavelength of 780 to 2100nm of the first laminated glass member is higher than the infrared raytransmittance in the wavelength of 780 to 2100 nm of the secondlaminated glass member.
 15. The laminated glass according to claim 14,wherein the infrared ray transmittance in the wavelength of 780 to 2100nm of the first laminated glass member is higher by 10% or more than theinfrared ray transmittance in the wavelength of 780 to 2100 nm of thesecond laminated glass member.
 16. (canceled)
 17. The laminated glassaccording to claim 13, wherein the first laminated glass member and thesecond laminated glass member each are a clear glass other than a heatray-absorbing plate glass.
 18. The laminated glass according to claim13, wherein the first laminated glass member and the second laminatedglass member each are a heat ray-absorbing plate glass.
 19. Thelaminated glass according to claim 13, wherein the infrared raytransmittance in the wavelength of 780 to 2100 nm of the first resinlayer is higher by 30% or more than the infrared ray transmittance inthe wavelength of 780 to 2100 nm of the second resin layer.
 20. Thelaminated glass according to claim 13, wherein the infrared rayreflection layer is a resin film with metal foil, a multilayer laminatedfilm in which a metal layer and a dielectric layer are formed on a resinlayer, a multilayer resin film or a liquid crystal film.
 21. Thelaminated glass according to claim 13, wherein at least one among thefirst resin layer and the second resin layer contains an adhesive forceregulating agent.
 22. The laminated glass according to claim 13, whereinboth of the first resin layer and the second resin layer contain anadhesive force regulating agent.
 23. The laminated glass according toclaim 13, wherein the second resin layer contains metal oxide particles.24. The laminated glass according to claim 23, wherein the metal oxideparticles are tin-doped indium oxide particles or tungsten oxideparticles.
 25. The laminated glass according to claim 23, wherein thesecond resin layer contains at least one kind among a phthalocyaninecompound, a naphthalocyanine compound and an anthracyanine compound. 26.The laminated glass according to claim 23, wherein the thermoplasticresin in the first resin layer is a polyvinyl acetal resin and thethermoplastic resin in the second resin layer is a polyvinyl acetalresin.
 27. The laminated glass according to claim 23, wherein the firstresin layer contains a plasticizer and the second resin layer contains aplasticizer.
 28. The laminated glass according to claim 23, wherein thefirst resin layer contains an ultraviolet ray shielding agent.
 29. Thelaminated glass according to claim 23, wherein the second resin layercontains an ultraviolet ray shielding agent.
 30. The laminated glassaccording to claim 23, wherein the second resin layer further containsheat shielding particles, and a content of the heat shielding particlesin the second resin layer is greater than or equal to 0.01% by weight.31. The laminated glass according to claim 23, wherein the heatshielding particles in the second resin layer contain tungsten oxideparticles.